Self Transcranial Direct Current Stimulation for Pain in Older Adults With Knee Osteoarthritis

• Sponsor: The University of Texas Health Science Center, Houston (Other)
• Overall Status: Completed
• CT.gov ID: NCT03425019
• Collaborator: (none)
• Enrollment: 21
• Location: 1
• Arm: 1
• Actual Duration (Months): 6.7
• Patients Per Site Per Month: 3.1

Study Details

Study Description

Brief Summary

The purpose of this study is to determine the feasibility and preliminary efficacy of two weeks of self Transcranial Direct Current Stimulation (tDCS) for pain in older patients with knee osteoarthritis (OA).

Condition or Disease	Intervention/Treatment	Phase
Knee Osteoarthritis; Chronic Pain	Device: Soterix 1x1 tDCS mini-CT Stimulator device	N/A

Study Design

• Study Type: Interventional
• Actual Enrollment: 21 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: Self Transcranial Direct Current Stimulation for Pain in Older Adults With Knee Osteoarthritis (Self tDCS and Knee Pain)
• Actual Study Start Date: Mar 14, 2018
• Actual Primary Completion Date: Oct 5, 2018
• Actual Study Completion Date: Oct 5, 2018

Arms and Interventions

Arm

Intervention/Treatment

Experimental: Transcranial Direct Current Stimulation Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.

Device: Soterix 1x1 tDCS mini-CT Stimulator device; Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.

Outcome Measures

Primary Outcome Measures

1. Clinical Pain Intensity as Assessed by a Visual Analogue Scale (VAS) [baseline]

   Scores on the visual analogue scale (VAS) range from 0 (no pain) to 100 (worst pain imaginable).

2. Clinical Pain Intensity as Assessed by a Visual Analogue Scale (VAS) [2 weeks]

   Scores on the visual analogue scale (VAS) range from 0 (no pain) to 100 (worst pain imaginable).

Secondary Outcome Measures

1. Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Pain Subscale [baseline]

   The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.

2. Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Pain Subscale [2 weeks]

   The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.

3. Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Stiffness Subscale [baseline]

   The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.

4. Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Stiffness Subscale [2 weeks]

   The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.

5. Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Functional Impairment Subscale [baseline]

   The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.

6. Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Functional Impairment Subscale [2 weeks]

   The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.

7. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Continuous Pain Summary Scale [baseline]

   The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The continuous pain subscale assesses throbbing pain, cramping pain, gnawing pain, aching pain, heavy pain, and tender, and total score on the continuous pain subscale ranges from 0-60, with a higher score indicating worse pain.

8. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Continuous Pain Subscale [2 weeks]

   The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The continuous pain subscale assesses throbbing pain, cramping pain, gnawing pain, aching pain, heavy pain, and tender, and total score on the continuous pain subscale ranges from 0-60, with a higher score indicating worse pain.

9. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Intermittent Pain Subscale [baseline]

   The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The intermittent pain subscale assesses shooting pain, stabbing pain, sharp pain, splitting pain, electric-shock pain, and piercing, and total score on the intermittent pain subscale ranges from 0-60, with a higher score indicating worse pain.

10. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Intermittent Pain Subscale [2 weeks]

    The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The intermittent pain subscale assesses shooting pain, stabbing pain, sharp pain, splitting pain, electric-shock pain, and piercing, and total score on the intermittent pain subscale ranges from 0-60, with a higher score indicating worse pain.

11. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Neuropathic Pain Subscale [baseline]

    The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The neuropathic pain subscale assesses hot-burning pain, cold-freezing pain, pain caused by light touch, itching, tingling or 'pins and needles', and numbness, and total score on the neuropathic pain subscale ranges from 0-60, with a higher score indicating worse pain.

12. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Neuropathic Pain Subscale [2 weeks]

    The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The neuropathic pain subscale assesses hot-burning pain, cold-freezing pain, pain caused by light touch, itching, tingling or 'pins and needles', and numbness, and total score on the neuropathic pain subscale ranges from 0-60, with a higher score indicating worse pain.

13. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Affective Description Subscale [baseline]

    The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The affective description subscale assesses tiring-exhausting, sickening, fearful, and punishing-cruel, and total score on the affective description subscale ranges from 0-40, with a higher score indicating worse pain.

14. Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Affective Description Subscale [2 weeks]

    The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The affective description subscale assesses tiring-exhausting, sickening, fearful, and punishing-cruel, and total score on the affective description subscale ranges from 0-40, with a higher score indicating worse pain.

15. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Threshold (HPTH) [baseline]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTH, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when the sensation ''first becomes painful" to assess the heat pain threshold (HPTH). The temperature at which participants pressed the button to indicate the sensation ''first becomes painful" is reported.

16. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Threshold (HPTH) [2 weeks]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTH, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when the sensation ''first becomes painful" to assess the heat pain threshold (HPTH). The temperature at which participants pressed the button to indicate the sensation ''first becomes painful" is reported.

17. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Tolerance (HPTO) [baseline]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTO, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when they ''no longer feel able to tolerate the pain." The temperature at which participants pressed the button to indicate they could ''no longer feel able to tolerate the pain" is reported.

18. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Tolerance (HPTO) [2 weeks]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTO, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when they ''no longer feel able to tolerate the pain." The temperature at which participants pressed the button to indicate they could ''no longer feel able to tolerate the pain" is reported.

19. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Pressure Pain Threshold (PPT) [baseline]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's medial knee, lateral knee, or trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.

20. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Pressure Pain Threshold (PPT) [2 weeks]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's medial knee, lateral knee, or trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.

21. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Punctate Mechanical Pain (PMP) [baseline]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PMP, punctate mechanical pain is delivered to the patella or hand by a calibrated nylon monofilament for 10 contacts of the monofilament at one contact per second. Participants rate the pain intensity on a scale from 0 (no pain) to 100 (maximum imaginable pain).

22. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Punctate Mechanical Pain (PMP) [2 weeks]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PMP, punctate mechanical pain is delivered to the patella or hand by a calibrated nylon monofilament for 10 contacts of the monofilament at one contact per second. Participants rate the pain intensity on a scale from 0 (no pain) to 100 (maximum imaginable pain).

23. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Conditioned Pain Modulation (CPM) [baseline]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). CPM is reported as the change in PPT before and immediately following immersion of the contralateral hand up to the wrist in a cold water bath (12 degrees Celsius) for up to one minute. To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.

24. Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Conditioned Pain Modulation (CPM) [2 weeks]

    In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). CPM is reported as the change in PPT before and immediately following immersion of the contralateral hand up to the wrist in a cold water bath (12 degrees Celsius) for up to one minute. To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.

25. Number of Participants Who Were Assessed by Functional Near-infrared Spectroscopy (fNIRS) [2 weeks]

    Pain-related cortical response will be measured using a continuous-wave, multichannel fNIRS imaging system (LIGHTNIRS, Shimadzu, Kyoto, Japan) with three semiconductor lasers at 780, 805, and 830 nm. Optical recordings will be collected during thermal pain stimulation.

26. Feasibility as Assessed by a Survey of Participants' tDCS Experience - Ease of Using Device [2 weeks]

    Data will be collected on participants' tDCS experience at the conclusion of tDCS treatment on a scale of 0 (strongly disagree) to 10 (strongly agree): Q1) "Overall the device was easy to use"

27. Feasibility as Assessed by a Survey of Participants' tDCS Experience - Ease of Preparation of Device [2 weeks]

    Data will be collected on participants' tDCS experience at the conclusion of tDCS treatment on a scale of 0 (strongly disagree) to 10 (strongly agree): Q2) "It was easy to prepare the device and accessories"

28. Feasibility as Assessed by a Survey of Participants' tDCS Experience - Effectiveness of Treatment Over Time [2 weeks]

    Data will be collected on participants' tDCS experience at the conclusion of tDCS treatment on a scale of 0 (strongly disagree) to 10 (strongly agree): Q3) "The effectiveness of the treatment increased over the course of treatment."

29. Tolerability as Assessed by Number of Participants With Side Effects [2 weeks]

    The participants will be asked in an open-ended manner whether they have experienced any side effects, and they will then be asked specifically about tingling, itching sensation, burning sensation, pain at the stimulation site, fatigue, nervousness, headache, difficulty concentrating, mood change, and changes in vision or visual perception.

30. Anxiety as Assessed by the PROMIS Anxiety-short Form [baseline]

    The 7-item PROMIS anxiety-short form assesses the pure domain of anxiety in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 7 to 35 with higher scores indicating greater severity of anxiety.

31. Anxiety as Assessed by the PROMIS Anxiety-short Form [2 weeks]

    The 7-item PROMIS anxiety-short form assesses the pure domain of anxiety in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 7 to 35 with higher scores indicating greater severity of anxiety.

32. Depression as Assessed by the PROMIS Depression-short Form [baseline]

    The 8-item PROMIS depression-short form assesses the pure domain of depression in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of depression.

33. Depression as Assessed by the PROMIS Depression-short Form [2 weeks]

    The 8-item PROMIS depression-short form assesses the pure domain of depression in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of depression.

34. Sleep Disturbance as Assessed by the PROMIS Sleep Disturbance-short Form [baseline]

    The 8-item PROMIS sleep disturbance-short form assesses the pure domain of sleep disturbance in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of sleep disturbance.

35. Sleep Disturbance as Assessed by the PROMIS Sleep Disturbance-short Form [2 weeks]

    The 8-item PROMIS sleep disturbance-short form assesses the pure domain of sleep disturbance in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of sleep disturbance.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 50 Years to 80 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Inclusion Criteria:

• have self-reported unilateral or bilateral knee OA pain, according to American College of Rheumatology criteria

• have had knee OA pain in the past 3 months with an average of at least 3 on a 10 cm Visual Analog Scale (VAS) for pain

• can speak and read English

• have a device with internet access that can be used for secure video conferencing for real-time remote supervision

• have access to a distraction-free, well lit, clean environment with a safe area to store the device and device kit

• have no plan to change medication regimens for pain throughout the trial

• are able to travel to the coordinating center

• are willing and able to provide written informed consent prior to enrollment.

Exclusion Criteria:

• previous prosthetic knee replacement or non-arthroscopic surgery to the affected knee

• history of brain surgery, tumor, seizure, stroke, or intracranial metal implantation

• systemic rheumatic disorders, including rheumatoid arthritis, systemic lupus erythematosus, and fibromyalgia

• uncontrolled hypertension (i.e., systolic blood pressure/ diastolic blood pressure ≥ 150/95 mm Hg)

• heart failure

• history of acute myocardial infarction

• peripheral neuropathy

• alcohol/substance abuse

• cognitive impairment (i.e., Mini-Mental Status Exam score ≤ 23)

• pregnancy or lactation

• hospitalization within the preceding year for psychiatric illness

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	The University of Texas Health Science Center at Houston	Houston	Texas	United States	77030

Sponsors and Collaborators

• The University of Texas Health Science Center, Houston

Investigators

• Principal Investigator: Hyochol Ahn, PhD, The University of Texas Health Science Center, Houston

Study Documents (Full-Text)

• Study Protocol and Statistical Analysis Plan - Mar 7, 2018

More Information

Publications

None provided.

• Responsible Party: Hyochol Ahn, Associate Professor, The University of Texas Health Science Center, Houston
• ClinicalTrials.gov Identifier: NCT03425019
• Other Study ID Numbers: HSC-SN-17-1072
• First Posted: Feb 7, 2018
• Last Update Posted: Oct 15, 2021
• Last Verified: Sep 1, 2021

• Individual Participant Data (IPD) Sharing Statement: No
• Plan to Share IPD: No
• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: Yes
• Product Manufactured in and Exported from the U.S.: No
• Keywords provided by Hyochol Ahn, Associate Professor, The University of Texas Health Science Center, Houston: Knee Osteoarthritis; Chronic Pain; Osteoarthritis; Transcranial Direct Current Stimulation; tDCS
• Additional relevant MeSH terms: Osteoarthritis; Osteoarthritis, Knee; Chronic Pain

Study Results

Participant Flow

Pre-assignment Detail	1 participant withdrew before the intervention started.

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Period Title: Overall Study
STARTED	20
COMPLETED	20
NOT COMPLETED	0

Baseline Characteristics

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Overall Participants	20
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	61.2 (7.23)
Sex: Female, Male (Count of Participants)
Female	15 75%
Male	5 25%
Race/Ethnicity, Customized (Count of Participants)
African American	6 30%
Asian	6 30%
Hispanic	1 5%
White	7 35%
Region of Enrollment (Count of Participants)
United States	20 100%
Education (Count of Participants)
High School	3 15%
2-year college	5 25%
4-year college	9 45%
Master's degree	2 10%
Doctoral degree	1 5%
Body Mass Index (BMI) (kg/m^2) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [kg/m^2]	28.33 (8.01)
Osteoarthritis duration (months) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [months]	29.60 (26.17)

Outcome Measures

1. Primary Outcome

Title	Clinical Pain Intensity as Assessed by a Visual Analogue Scale (VAS)
Description	Scores on the visual analogue scale (VAS) range from 0 (no pain) to 100 (worst pain imaginable).
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	55.23 (25.45)

2. Primary Outcome

Title	Clinical Pain Intensity as Assessed by a Visual Analogue Scale (VAS)
Description	Scores on the visual analogue scale (VAS) range from 0 (no pain) to 100 (worst pain imaginable).
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	24.85 (22.70)

3. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Pain Subscale
Description	The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [score on a scale]	7.95 (4.39)

4. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Pain Subscale
Description	The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	5.75 (4.25)

5. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Stiffness Subscale
Description	The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	4.00 (1.86)

6. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Stiffness Subscale
Description	The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	2.90 (1.74)

7. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Functional Impairment Subscale
Description	The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	29.10 (17.53)

8. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) - Functional Impairment Subscale
Description	The WOMAC is a self-administered questionnaire consisting of 3 subscales related to pain (pain subscale total score range, 0-20), stiffness (stiffness subscale total score range, 0-8), and impairments of physical function (functional impairment subscale range, 0-68), with higher scores indicating worse pain, stiffness, and impairments of physical function, respectively.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	20.85 (15.22)

9. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Continuous Pain Summary Scale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The continuous pain subscale assesses throbbing pain, cramping pain, gnawing pain, aching pain, heavy pain, and tender, and total score on the continuous pain subscale ranges from 0-60, with a higher score indicating worse pain.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	22.75 (15.26)

10. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Continuous Pain Subscale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The continuous pain subscale assesses throbbing pain, cramping pain, gnawing pain, aching pain, heavy pain, and tender, and total score on the continuous pain subscale ranges from 0-60, with a higher score indicating worse pain.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	14.05 (13.84)

11. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Intermittent Pain Subscale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The intermittent pain subscale assesses shooting pain, stabbing pain, sharp pain, splitting pain, electric-shock pain, and piercing, and total score on the intermittent pain subscale ranges from 0-60, with a higher score indicating worse pain.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	17.80 (16.18)

12. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Intermittent Pain Subscale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The intermittent pain subscale assesses shooting pain, stabbing pain, sharp pain, splitting pain, electric-shock pain, and piercing, and total score on the intermittent pain subscale ranges from 0-60, with a higher score indicating worse pain.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	12.90 (15.80)

13. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Neuropathic Pain Subscale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The neuropathic pain subscale assesses hot-burning pain, cold-freezing pain, pain caused by light touch, itching, tingling or 'pins and needles', and numbness, and total score on the neuropathic pain subscale ranges from 0-60, with a higher score indicating worse pain.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	11.1 (13.71)

14. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Neuropathic Pain Subscale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The neuropathic pain subscale assesses hot-burning pain, cold-freezing pain, pain caused by light touch, itching, tingling or 'pins and needles', and numbness, and total score on the neuropathic pain subscale ranges from 0-60, with a higher score indicating worse pain.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	8.2 (14.23)

15. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Affective Description Subscale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The affective description subscale assesses tiring-exhausting, sickening, fearful, and punishing-cruel, and total score on the affective description subscale ranges from 0-40, with a higher score indicating worse pain.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	11.7 (11.65)

16. Secondary Outcome

Title	Clinical Pain Intensity as Assessed by Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) - Affective Description Subscale
Description	The SF-MPQ-2 measures the quality as well as the intensity of pain. Participants complete the SF-MPQ-2 by rating the extent to which they experienced each of 22 pain descriptors in the past week using an 11-point numeric rating scale (0 = "none" to 10 = "worst possible"). The affective description subscale assesses tiring-exhausting, sickening, fearful, and punishing-cruel, and total score on the affective description subscale ranges from 0-40, with a higher score indicating worse pain.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	5.75 (10.40)

17. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Threshold (HPTH)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTH, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when the sensation ''first becomes painful" to assess the heat pain threshold (HPTH). The temperature at which participants pressed the button to indicate the sensation ''first becomes painful" is reported.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
arm	37.9 (3.3)
knee	39.1 (3.5)

18. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Threshold (HPTH)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTH, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when the sensation ''first becomes painful" to assess the heat pain threshold (HPTH). The temperature at which participants pressed the button to indicate the sensation ''first becomes painful" is reported.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
arm	37.3 (2.0)
knee	40.1 (3.4)

19. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Tolerance (HPTO)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTO, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when they ''no longer feel able to tolerate the pain." The temperature at which participants pressed the button to indicate they could ''no longer feel able to tolerate the pain" is reported.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
arm	43.2 (3.1)
knee	43.1 (3.3)

20. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Heat Pain Tolerance (HPTO)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess HPTO, heat stimuli were delivered to the participant's arm or knee using a computer-controlled TSAII NeuroSensory Analyzer. From a baseline of 32 degrees Celsius, the temperature increased by 0.5 degrees Celsius per second until the participants responded by pressing a button to stop heat stimuli. Participants were instructed to press the button when they ''no longer feel able to tolerate the pain." The temperature at which participants pressed the button to indicate they could ''no longer feel able to tolerate the pain" is reported.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
arm	43.2 (3.2)
knee	44.6 (3.1)

21. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Pressure Pain Threshold (PPT)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's medial knee, lateral knee, or trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
medial knee	3.2 (1.4)
lateral knee	3.5 (1.5)
trapezius	2.9 (1.6)

22. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Pressure Pain Threshold (PPT)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's medial knee, lateral knee, or trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
medial knee	3.7 (1.2)
lateral knee	4.4 (1.3)
trapezius	3.9 (1.3)

23. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Punctate Mechanical Pain (PMP)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PMP, punctate mechanical pain is delivered to the patella or hand by a calibrated nylon monofilament for 10 contacts of the monofilament at one contact per second. Participants rate the pain intensity on a scale from 0 (no pain) to 100 (maximum imaginable pain).
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
patella	84.7 (23.4)
hand	66.0 (27.0)

24. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Punctate Mechanical Pain (PMP)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). To assess PMP, punctate mechanical pain is delivered to the patella or hand by a calibrated nylon monofilament for 10 contacts of the monofilament at one contact per second. Participants rate the pain intensity on a scale from 0 (no pain) to 100 (maximum imaginable pain).
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
patella	67.4 (26.9)
hand	54.6 (23.9)

25. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Conditioned Pain Modulation (CPM)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). CPM is reported as the change in PPT before and immediately following immersion of the contralateral hand up to the wrist in a cold water bath (12 degrees Celsius) for up to one minute. To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [kilograms force (kgf)]	0.9 (0.7)

26. Secondary Outcome

Title	Experimental Pain Sensitivity as Assessed by a Multimodal Quantitative Sensory Testing (QST) Battery - Conditioned Pain Modulation (CPM)
Description	In order to measure experimental pain sensitivity, a multimodal Quantitative Sensory Testing (QST) battery will be completed: heat pain threshold (HPTH); heat pain tolerance (HPTO), pressure pain threshold (PPT), punctate mechanical pain (PMP), and Conditioned Pain Modulation (CPM). CPM is reported as the change in PPT before and immediately following immersion of the contralateral hand up to the wrist in a cold water bath (12 degrees Celsius) for up to one minute. To assess PPT, a handheld digital pressure algometer (Wagner, Greenwich, CT) was applied at a constant rate of 0.3 kilograms force per centimeter squared (kgf/cm^2) per second to the participant's trapezius. Participants were asked to notify the experimenter when the pressure sensation ''first becomes painful." The pressure at which participants pressed the button to indicate that the pressure sensation ''first becomes painful" is reported.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [kilograms force (kgf)]	1.3 (0.6)

27. Secondary Outcome

Title	Number of Participants Who Were Assessed by Functional Near-infrared Spectroscopy (fNIRS)
Description	Pain-related cortical response will be measured using a continuous-wave, multichannel fNIRS imaging system (LIGHTNIRS, Shimadzu, Kyoto, Japan) with three semiconductor lasers at 780, 805, and 830 nm. Optical recordings will be collected during thermal pain stimulation.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Count of Participants [Participants]	20 100%

28. Secondary Outcome

Title	Feasibility as Assessed by a Survey of Participants' tDCS Experience - Ease of Using Device
Description	Data will be collected on participants' tDCS experience at the conclusion of tDCS treatment on a scale of 0 (strongly disagree) to 10 (strongly agree): Q1) "Overall the device was easy to use"
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [score on a scale]	9.75 (0.44)

29. Secondary Outcome

Title	Feasibility as Assessed by a Survey of Participants' tDCS Experience - Ease of Preparation of Device
Description	Data will be collected on participants' tDCS experience at the conclusion of tDCS treatment on a scale of 0 (strongly disagree) to 10 (strongly agree): Q2) "It was easy to prepare the device and accessories"
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [score on a scale]	9.75 (0.44)

30. Secondary Outcome

Title	Feasibility as Assessed by a Survey of Participants' tDCS Experience - Effectiveness of Treatment Over Time
Description	Data will be collected on participants' tDCS experience at the conclusion of tDCS treatment on a scale of 0 (strongly disagree) to 10 (strongly agree): Q3) "The effectiveness of the treatment increased over the course of treatment."
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [score on a scale]	6.75 (3.17)

31. Secondary Outcome

Title	Tolerability as Assessed by Number of Participants With Side Effects
Description	The participants will be asked in an open-ended manner whether they have experienced any side effects, and they will then be asked specifically about tingling, itching sensation, burning sensation, pain at the stimulation site, fatigue, nervousness, headache, difficulty concentrating, mood change, and changes in vision or visual perception.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 milliamps (mA) will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff. Soterix 1x1 tDCS mini-CT Stimulator device: Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Count of Participants [Participants]	0 0%

32. Secondary Outcome

Title	Anxiety as Assessed by the PROMIS Anxiety-short Form
Description	The 7-item PROMIS anxiety-short form assesses the pure domain of anxiety in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 7 to 35 with higher scores indicating greater severity of anxiety.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [score on a scale]	13.6 (6.73)

33. Secondary Outcome

Title	Anxiety as Assessed by the PROMIS Anxiety-short Form
Description	The 7-item PROMIS anxiety-short form assesses the pure domain of anxiety in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 7 to 35 with higher scores indicating greater severity of anxiety.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [score on a scale]	12.05 (6.86)

34. Secondary Outcome

Title	Depression as Assessed by the PROMIS Depression-short Form
Description	The 8-item PROMIS depression-short form assesses the pure domain of depression in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of depression.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	12.3 (7.69)

35. Secondary Outcome

Title	Depression as Assessed by the PROMIS Depression-short Form
Description	The 8-item PROMIS depression-short form assesses the pure domain of depression in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of depression.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	11.85 (6.98)

36. Secondary Outcome

Title	Sleep Disturbance as Assessed by the PROMIS Sleep Disturbance-short Form
Description	The 8-item PROMIS sleep disturbance-short form assesses the pure domain of sleep disturbance in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of sleep disturbance.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	24.3 (7.87)

37. Secondary Outcome

Title	Sleep Disturbance as Assessed by the PROMIS Sleep Disturbance-short Form
Description	The 8-item PROMIS sleep disturbance-short form assesses the pure domain of sleep disturbance in individuals age 18 and older, and each item on the measure is rated on a 5-point scale (1=never; 2=rarely; 3=sometimes; 4=often; and 5=always) with a range in score from 8 to 40 with higher scores indicating greater severity of sleep disturbance.
Time Frame	2 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
Measure Participants	20
Mean (Standard Deviation) [units on a scale]	19.85 (8.10)

Adverse Events

Time Frame	2 weeks
Arm/Group Title	Transcranial Direct Current Stimulation
Arm/Group Description	Transcranial Direct Current Stimulation (tDCS) involves the application of weak direct electric current to the head in a noninvasive and painless manner. tDCS with a constant current intensity of 2 mA will be applied for 20 minutes per session daily for 2 weeks (Monday to Friday) via the Soterix 1x1 tDCS mini-CT Stimulator device. Participants will self-administer tDCS at their home or a private room for two weeks (Mondays-Fridays) under real-time supervision by the research staff.
All Cause Mortality
	Transcranial Direct Current Stimulation
	Affected / at Risk (%)	# Events
Total	0/20 (0%)
Serious Adverse Events
	Transcranial Direct Current Stimulation
	Affected / at Risk (%)	# Events
Total	0/20 (0%)
Other (Not Including Serious) Adverse Events
	Transcranial Direct Current Stimulation
	Affected / at Risk (%)	# Events
Total	0/20 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.