BEHOLD-16: A Psychological-behavioral Intervention to Increase Activity in Type 2 Diabetes

• Sponsor: Massachusetts General Hospital (Other)
• Overall Status: Completed
• CT.gov ID: NCT03164538
• Collaborator: (none)
• Enrollment: 70
• Location: 1
• Arms: 2
• Actual Duration (Months): 26.5
• Patients Per Site Per Month: 2.6

Study Details

Study Description

Brief Summary

The focus of this study is to examine the feasibility, acceptability, and impact of a customized, combined positive psychology and motivational interviewing (PP-MI) health behavior intervention in a group of patients with type 2 diabetes (T2D).

Condition or Disease	Intervention/Treatment	Phase
Type 2 Diabetes Mellitus	Behavioral: Positive Psychology + Motivational Interviewing; Behavioral: Diabetes Education	N/A

Detailed Description

The investigators will compare a combined positive psychology and motivational interviewing (PP-MI) intervention that is adapted for patients with T2D to a diabetes education intervention (control) in a randomized controlled trial. The investigators will enroll 70 participants, who will be randomized to either a 16-week PP-MI health behavior intervention or an 16-week diabetes education intervention.

In this project, the investigators plan to do the following:

1. Examine the feasibility and acceptability of a 16-week, telephone-delivered health behavior intervention utilizing PP exercises and MI with systematic goal-setting.

2. Determine whether the PP-MI intervention leads to greater increases in physical activity than the education intervention in T2D patients.

3. Explore the impact of the PP-MI intervention on other psychological, behavioral, and medical outcomes, compared to the education intervention.

Participants will undergo an initial screening visit during which they will meet with study staff in person. At this visit, study eligibility will be confirmed, and eligible and willing participants will be enrolled. Following enrollment, participants will complete self-report measures, and vital signs and A1c will be measured. They then will take home and wear an accelerometer for one week, to measure baseline physical activity.

Baseline information about enrolled participants will be obtained from the participants, care providers, and the electronic medical record as required for characterization of the population. This information will include data regarding medical history (type 2 diabetes mellitus), current medical variables (conditions affecting physical activity), medications, and sociodemographic data (age, gender, race/ethnicity, living alone).

Participants will undergo a second in-person visit once adequate baseline physical activity data has been obtained. In this visit, accelerometer data will be reviewed to ensure that adequate baseline activity was captured. If so, participants will be randomized to either the PP-MI or diabetes education condition, then begin the study intervention. During this second in-person visit, participants will receive either a PP-MI or diabetes education treatment manual, depending on randomization.

For the PP-MI intervention:

For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. At subsequent sessions, participants will review the prior week's PP exercise and learn about a new exercise, then will review the prior week's physical activity goal and set a new one.

For the diabetes education intervention:

Each week, participants will learn about a different health behavior topic related to diabetes health. This includes information about diabetes self-monitoring, medication adherence, having a heart-healthy diet, and being physically active.

Participants will complete the remaining sessions by phone approximately weekly over the next 16 weeks. Phone sessions will last approximately 30 minutes, with PP-MI and physical activity assignments completed between phone sessions. PP and MI will be delivered step-wise within sessions (rather than intertwined) based on our experience, participant feedback, and pilot work. If a week is missed, the session will not be skipped, but rather the intervention will be completed sequentially (with participants who miss weeks then missing the final sessions), with the exception of the final visit, which skips to Planning for the Future in all cases.

Participants will undergo an in-person follow-up assessment at 16 weeks. At this session, participants will repeat self-report assessments that were administered at baseline. Vital signs and a blood sample will again be collected at this in-person visit. Prior to this assessment, participants will wear an accelerometer for 7 days to measure physical activity. Participants will also undergo a phone follow-up assessment at 24 weeks. During this session over the phone, participants will repeat self-report assessments that were administered at baseline. Finally, prior to this follow-up, participants will wear another accelerometer for 7 days to measure physical activity.

Study Design

• Study Type: Interventional
• Actual Enrollment: 70 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Single (Outcomes Assessor)
• Primary Purpose: Treatment
• Official Title: A Psychological-behavioral Intervention to Increase Activity in Type 2 Diabetes: a 16-week Randomized Controlled Trial
• Actual Study Start Date: Jul 25, 2017
• Actual Primary Completion Date: Oct 10, 2019
• Actual Study Completion Date: Oct 10, 2019

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Positive Psychology + Motivational Interviewing Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting.	Behavioral: Positive Psychology + Motivational Interviewing; Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions. PP and MI components will be delivered stepwise within sessions (rather than intertwined).
Active Comparator: Diabetes Education Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet).	Behavioral: Diabetes Education; Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.

Outcome Measures

Primary Outcome Measures

1. Number of PP-MI Sessions Completed by Participants [16 weeks]

   Measured by number of PP-MI sessions completed by participants in the PP-MI group.

Secondary Outcome Measures

1. Ease of PP Component [Weeks 1-16]

   Participants in the PP-MI group will provide ratings of ease after each PP exercise, measured on a 10-point Likert scale (0=very difficult; 10=very easy). Weekly ratings were averaged to provide an overall ease of the exercises.

2. Ease of MI Component [Weeks 1-16]

   Participants in the PP-MI group will provide ratings of ease after each MI exercise, measured on a 10-point Likert scale (0=very difficult; 10=very easy). Weekly ratings were averaged to provide an overall ease of the exercises.

3. Utility of PP Component [Weeks 1-16]

   Participants in the PP-MI group will provide ratings of utility after each PP exercise, measured on a 10-point Likert scale (0=not at all helpful; 10=very helpful). Weekly utility ratings were averaged to provide an overall utility score of the exercises.

4. Utility of MI Component [Weeks 1-16]

   Participants in the PP-MI group will provide ratings of utility after each MI exercise, measured on a 10-point Likert scale (0=not at all helpful; 10=very helpful). Weekly utility ratings were averaged to provide an overall utility score of the exercises.

5. Change in Moderate-Vigorous Physical Activity [Change from Baseline to 16 weeks, and Baseline to 24 weeks]

   ActiGraph GT3X+ step counters are validated as measures of physical activity and have been used in numerous studies of physical activity in patients with medical illness. In this trial, participants will wear the accelerometer for one week at baseline, 16 weeks, and 24 weeks to assess the feasibility of doing so and to ensure adequate capture of physical activity.

6. Change in Physical Activity [Change from Baseline to 16 weeks, and Baseline to 24 weeks]

   Measured by Actigraph accelerometer, in number of steps per day.

7. Change in Sedentary Time [Change from Baseline to 16 weeks, and Baseline to 24 weeks]

   Measured by Actigraph accelerometer, in minutes per day.

8. Change in Positive Affect [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

   The positive affect items on the Positive and Negative Affect Schedule (PANAS), a well-validated scale used in other intervention trials and in patients with medical illnesses, will be used to measure positive affect (Range: 10-50). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of positive affect.

9. Change in Optimism [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

   Life Orientation Test-Revised is a well-validated 6-item instrument used to measure dispositional optimism (Range: 0-24). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of optimism.

10. Change in Self-Efficacy for Exercise [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

    Measured by the Self-Efficacy for Exercise scale (SEE), a validated scale which assess self-efficacy barriers to exercise (Range: 0-90). Higher scores indicate higher efficacy expectations in relation to exercising. This was measured at Baseline, Week 16, and Week 24.

11. Change in Depression [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

    The Hospital Anxiety and Depression Scale (HADS)-depression subscale was be used to measure depression. This is a well-validated scale with few somatic symptom items that can confound mood/anxiety assessment in medically-ill patients (Range: 0-21). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of depression.

12. Change in Anxiety [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

    The Hospital Anxiety and Depression Scale (HADS)-anxiety subscale was be used to measure anxiety. This is a well-validated scale with few somatic symptom items that can confound mood/anxiety assessment in medically-ill patients (Range: 0-21). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of anxiety.

13. Change in Resilience [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

    Measured by the Brief Resilience Scale (BRS), a reliable scale which assesses a person's ability to recover from stress despite adversity (Range: 6-30). Higher scores indicate more resilience.

14. Change in Perceived Social Support [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

    Measured by the Multidimensional Scale of Perceived Social Support (MSPSS), a scale that measures subjectively reported social support (Range: 12-84). Higher scores indicate more subjectively reported social support.

15. Change in Diabetes Self-Care [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

    Measured by the Summary of Diabetes Self-Care Activities (SDSCA), a well-validated measure of diabetes self-management that is associated with clinical outcomes (Range: 0-7). Higher scores indicate more diabetes self-care activities.

Other Outcome Measures

1. Change in Medication Adherence [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

   Measured by Self-Reported Medication Adherence (SRMA), a two-item self-report medication adherence scale measuring percentage of time (in 10% increments) patients report taking their heart medications in the past one and two weeks. Minimum: 0, Maximum:100. Change was calculated by subtracting the score at baseline from the score at 16 weeks and 24 weeks. Higher scores indicate greater levels of medication adherence.

2. Change in Self-Reported Physical Activity [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

   Measured by the self-report International Physical Activity Questionnaire (IPAQ). The measure assesses the types of intensity of physical activity that people do as part of their daily lives. All activities are converted to multiples of resting energy expenditure (MET) minutes per week. Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks.

3. Change in Physical Function [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

   Measured by the 20-item short form of the Patient-Reported Outcomes Measurement Information System (PROMIS), a well-validated measure of physical function that is highly responsive to changes in a patient's physical function status (Range: 20-100). Higher scores indicate better physical function.

4. Change in Pain-Related Disability [Change in score from Baseline to 16 weeks, and Baseline to 24 weeks]

   Measured by the Pain Disability Index (PDI), a well-validated measure of the extent to which pain interferes with different daily activities (Range 0-70). Higher scores indicate greater interference from pain.

5. Change in Weight [Change from Baseline to Week 16]

   Measured during in-person visit at baseline and post-intervention.

6. Change in Body Mass Index (BMI) [Change from Baseline to Week 16]

   Measured during in-person visit at baseline and post-intervention.

7. Change in Blood Pressure (Systolic) [Change from Baseline to Week 16]

   Measured during in-person visit at baseline and post-intervention.

8. Change in Blood Pressure (Diastolic) [Change from Baseline to Week 16]

   Measured during in-person visit at baseline and post-intervention.

9. Change in Hemoglobin A1c [Change from Baseline to Week 16]

   Measured during in-person visit at baseline and post-intervention.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years and Older
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Inclusion Criteria:

1. T2D. Eligible patients will meet American Diabetes Association (ADA) criteria for T2D (e.g., HbA1c [A1C] ≥6.5%, fasting glucose ≥126 mg/d), with diagnosis confirmed by their diabetes clinician and/or medical record review.

2. Low physical activity. Low physical activity will be defined as ≤150 minutes/week of MVPA (corresponding to ADA recommendations for moderate or greater intensity aerobic physical activity). Physical activity will be measured using a brief questionnaire adapted from the International Physical Activity Questionnaire (IPAQ).

Exclusion Criteria:

1. Cognitive impairment precluding consent or meaningful participation.

2. Lack of phone availability.

3. Inability to read/write in English.

4. Additional medical conditions (e.g., severe arthritis) that preclude physical activity.

5. Enrollment in mind-body programs, lifestyle intervention programs (e.g., cardiac rehabilitation), or other clinical trials.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Massachusetts General Hospital	Boston	Massachusetts	United States	02114

Sponsors and Collaborators

• Massachusetts General Hospital

Investigators

• Principal Investigator: Jeff C Huffman, MD, Massachusetts General Hospital

Study Documents (Full-Text)

• Study Protocol and Statistical Analysis Plan - Apr 18, 2018

More Information

Publications

None provided.

• Responsible Party: Jeff C. Huffman, MD, Associate Chief of Psychiatry for Clinical Services, Massachusetts General Hospital
• ClinicalTrials.gov Identifier: NCT03164538
• Other Study ID Numbers: 2017P001113
• First Posted: May 23, 2017
• Last Update Posted: Feb 21, 2021
• Last Verified: Feb 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: No
• Additional relevant MeSH terms: Diabetes Mellitus; Diabetes Mellitus, Type 2

Study Results

Participant Flow

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Period Title: Overall Study
STARTED	35	35
COMPLETED	28	29
NOT COMPLETED	7	6

Baseline Characteristics

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education	Total
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.	Total of all reporting groups
Overall Participants	35	35	70
Age (Count of Participants)
<=18 years	0 0%	0 0%	0 0%
Between 18 and 65 years	19 54.3%	20 57.1%	39 55.7%
>=65 years	16 45.7%	15 42.9%	31 44.3%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	64.6 (10.2)	62.9 (10.7)	63.7 (10.4)
Sex: Female, Male (Count of Participants)
Female	16 45.7%	16 45.7%	32 45.7%
Male	19 54.3%	19 54.3%	38 54.3%
Ethnicity (NIH/OMB) (Count of Participants)
Hispanic or Latino	0 0%	3 8.6%	3 4.3%
Not Hispanic or Latino	35 100%	32 91.4%	67 95.7%
Unknown or Not Reported	0 0%	0 0%	0 0%
Race (NIH/OMB) (Count of Participants)
American Indian or Alaska Native	0 0%	0 0%	0 0%
Asian	5 14.3%	1 2.9%	6 8.6%
Native Hawaiian or Other Pacific Islander	0 0%	0 0%	0 0%
Black or African American	5 14.3%	2 5.7%	7 10%
White	24 68.6%	30 85.7%	54 77.1%
More than one race	0 0%	1 2.9%	1 1.4%
Unknown or Not Reported	1 2.9%	1 2.9%	2 2.9%
Moderate-Vigorous Physical Activity (minutes/day) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [minutes/day]	13.66 (13.15)	13.67 (12.12)	13.66 (12.55)
Physical Activity (steps/day) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [steps/day]	4706 (2389)	4805 (1993)	4756 (2184)
Sedentary Time (minutes/day) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [minutes/day]	551.40 (98.74)	499.66 (78.33)	525.53 (92.23)
Positive Affect (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	35.74 (6.87)	33.51 (7.54)	34.63 (7.25)
Optimism (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	15.94 (5.64)	17.20 (4.73)	16.57 (5.20)
Self-Efficacy for Exercise (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	50.06 (19.63)	55.43 (21.66)	52.74 (20.69)
Depression (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	3.63 (3.87)	4.00 (3.61)	3.81 (3.72)
Anxiety (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	5.37 (4.16)	5.60 (4.31)	5.49 (4.21)
Resilience (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	17.86 (2.32)	18.06 (1.63)	17.96 (1.99)
Perceived Social Support (MSPSS) (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	64.06 (18.25)	63.14 (18.25)	63.60 (18.12)
Diabetes Self-Care (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	3.17 (1.02)	2.27 (1.09)	2.72 (1.14)
Medication Adherence (percentage of medication taken) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [percentage of medication taken]	91 (22)	93 (14)	92 (18)
Self-Reported Physical Activity (MET minutes per week) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [MET minutes per week]	633.82 (560.97)	1914.87 (4374.98)	1274.34 (3162.72)
Physical Function (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	92.77 (5.50)	90.31 (10.92)	91.54 (8.67)
Pain-Related Disability (score on a scale) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [score on a scale]	8.77 (10.36)	13.71 (15.15)	11.20 (13.09)
Weight (pounds) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [pounds]	195.10 (34.02)	194.05 (40.85)	194.57 (37.32)
Body Mass Index (BMI) (kg/m^2) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [kg/m^2]	30.98 (4.47)	31.08 (5.58)	31.03 (5.02)
Blood Pressure (systolic) (millimeters of mercury) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [millimeters of mercury]	139.63 (11.31)	138.63 (13.97)	139.13 (12.63)
Blood Pressure (diastolic) (millimeters of mercury) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [millimeters of mercury]	73.34 (8.21)	74.09 (9.37)	73.71 (8.75)
Hemoglobin A1c (mg/dL) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [mg/dL]	7.72 (1.66)	7.75 (1.56)	7.73 (1.60)

Outcome Measures

1. Primary Outcome

Title	Number of PP-MI Sessions Completed by Participants
Description	Measured by number of PP-MI sessions completed by participants in the PP-MI group.
Time Frame	16 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.
Measure Participants	35
Mean (Standard Deviation) [sessions completed]	11 (4.45)

2. Secondary Outcome

Title	Ease of PP Component
Description	Participants in the PP-MI group will provide ratings of ease after each PP exercise, measured on a 10-point Likert scale (0=very difficult; 10=very easy). Weekly ratings were averaged to provide an overall ease of the exercises.
Time Frame	Weeks 1-16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.
Measure Participants	35
Mean (Standard Deviation) [units on a scale]	8.18 (1.98)

3. Secondary Outcome

Title	Ease of MI Component
Description	Participants in the PP-MI group will provide ratings of ease after each MI exercise, measured on a 10-point Likert scale (0=very difficult; 10=very easy). Weekly ratings were averaged to provide an overall ease of the exercises.
Time Frame	Weeks 1-16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.
Measure Participants	35
Mean (Standard Deviation) [units on a scale]	8.40 (1.83)

4. Secondary Outcome

Title	Utility of PP Component
Description	Participants in the PP-MI group will provide ratings of utility after each PP exercise, measured on a 10-point Likert scale (0=not at all helpful; 10=very helpful). Weekly utility ratings were averaged to provide an overall utility score of the exercises.
Time Frame	Weeks 1-16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.
Measure Participants	35
Mean (Standard Deviation) [units on a scale]	8.78 (1.51)

5. Secondary Outcome

Title	Utility of MI Component
Description	Participants in the PP-MI group will provide ratings of utility after each MI exercise, measured on a 10-point Likert scale (0=not at all helpful; 10=very helpful). Weekly utility ratings were averaged to provide an overall utility score of the exercises.
Time Frame	Weeks 1-16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.
Measure Participants	35
Mean (Standard Deviation) [units on a scale]	8.96 (1.40)

6. Secondary Outcome

Title	Change in Moderate-Vigorous Physical Activity
Description	ActiGraph GT3X+ step counters are validated as measures of physical activity and have been used in numerous studies of physical activity in patients with medical illness. In this trial, participants will wear the accelerometer for one week at baseline, 16 weeks, and 24 weeks to assess the feasibility of doing so and to ensure adequate capture of physical activity.
Time Frame	Change from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants wore the Actigraph and provided adequate data at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	35	35
16 weeks	3.88 (10.98)	-1.21 (9.76)
24 weeks	2.75 (10.31)	0.33 (12.09)

7. Secondary Outcome

Title	Change in Physical Activity
Description	Measured by Actigraph accelerometer, in number of steps per day.
Time Frame	Change from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants wore the Actigraph and provided adequate data.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	25	27
16 weeks	904 (1206)	-379 (1228)
24 weeks	222 (1410)	-290 (1301)

8. Secondary Outcome

Title	Change in Sedentary Time
Description	Measured by Actigraph accelerometer, in minutes per day.
Time Frame	Change from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants wore the Actigraph and provided adequate data.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	25	27
16 weeks	19.68 (138.82)	5.78 (74.75)
24 weeks	-11.84 (84.61)	4.74 (79.95)

9. Secondary Outcome

Title	Change in Positive Affect
Description	The positive affect items on the Positive and Negative Affect Schedule (PANAS), a well-validated scale used in other intervention trials and in patients with medical illnesses, will be used to measure positive affect (Range: 10-50). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of positive affect.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	1.29 (5.68)	0.41 (5.13)
24 weeks	5.54 (6.09)	4.21 (6.65)

10. Secondary Outcome

Title	Change in Optimism
Description	Life Orientation Test-Revised is a well-validated 6-item instrument used to measure dispositional optimism (Range: 0-24). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of optimism.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	2.54 (4.38)	0.55 (3.16)
24 weeks	2.54 (3.79)	0.43 (4.86)

11. Secondary Outcome

Title	Change in Self-Efficacy for Exercise
Description	Measured by the Self-Efficacy for Exercise scale (SEE), a validated scale which assess self-efficacy barriers to exercise (Range: 0-90). Higher scores indicate higher efficacy expectations in relation to exercising. This was measured at Baseline, Week 16, and Week 24.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	12.50 (22.66)	-9.55 (25.75)
24 weeks	7.38 (21.97)	-7.81 (27.47)

12. Secondary Outcome

Title	Change in Depression
Description	The Hospital Anxiety and Depression Scale (HADS)-depression subscale was be used to measure depression. This is a well-validated scale with few somatic symptom items that can confound mood/anxiety assessment in medically-ill patients (Range: 0-21). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of depression.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	-0.11 (3.19)	-0.72 (1.87)
24 weeks	0.00 (3.02)	0.46 (2.62)

13. Secondary Outcome

Title	Change in Anxiety
Description	The Hospital Anxiety and Depression Scale (HADS)-anxiety subscale was be used to measure anxiety. This is a well-validated scale with few somatic symptom items that can confound mood/anxiety assessment in medically-ill patients (Range: 0-21). Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks. Higher scores indicate higher levels of anxiety.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	-1.04 (3.98)	-0.90 (2.23)
24 weeks	-1.00 (3.44)	-0.96 (3.20)

14. Secondary Outcome

Title	Change in Resilience
Description	Measured by the Brief Resilience Scale (BRS), a reliable scale which assesses a person's ability to recover from stress despite adversity (Range: 6-30). Higher scores indicate more resilience.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	-0.07 (3.95)	0.00 (2.33)
24 weeks	-0.25 (2.64)	0.64 (2.33)

15. Secondary Outcome

Title	Change in Perceived Social Support
Description	Measured by the Multidimensional Scale of Perceived Social Support (MSPSS), a scale that measures subjectively reported social support (Range: 12-84). Higher scores indicate more subjectively reported social support.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	-1.18 (19.88)	3.83 (12.62)
24 weeks	6.25 (14.86)	5.57 (15.15)

16. Secondary Outcome

Title	Change in Diabetes Self-Care
Description	Measured by the Summary of Diabetes Self-Care Activities (SDSCA), a well-validated measure of diabetes self-management that is associated with clinical outcomes (Range: 0-7). Higher scores indicate more diabetes self-care activities.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed all follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	0.79 (0.93)	1.02 (1.03)
24 weeks	0.97 (0.92)	1.13 (1.20)

17. Other Pre-specified Outcome

Title	Change in Medication Adherence
Description	Measured by Self-Reported Medication Adherence (SRMA), a two-item self-report medication adherence scale measuring percentage of time (in 10% increments) patients report taking their heart medications in the past one and two weeks. Minimum: 0, Maximum:100. Change was calculated by subtracting the score at baseline from the score at 16 weeks and 24 weeks. Higher scores indicate greater levels of medication adherence.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	0.7 (5.4)	0.3 (7.8)
24 weeks	2.1 (4.1)	-0.4 (10.7)

18. Other Pre-specified Outcome

Title	Change in Self-Reported Physical Activity
Description	Measured by the self-report International Physical Activity Questionnaire (IPAQ). The measure assesses the types of intensity of physical activity that people do as part of their daily lives. All activities are converted to multiples of resting energy expenditure (MET) minutes per week. Change was calculated by subtracting the score at baseline from the score at 16 and 24 weeks.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed all follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	28
16 weeks	1512.41 (1957.69)	96.10 (1704.43)
24 weeks	912.72 (1096.29)	-87.80 (1585.93)

19. Other Pre-specified Outcome

Title	Change in Physical Function
Description	Measured by the 20-item short form of the Patient-Reported Outcomes Measurement Information System (PROMIS), a well-validated measure of physical function that is highly responsive to changes in a patient's physical function status (Range: 20-100). Higher scores indicate better physical function.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	29
16 weeks	0.04 (5.72)	0.31 (4.42)
24 weeks	2.83 (4.67)	0.96 (5.27)

20. Other Pre-specified Outcome

Title	Change in Pain-Related Disability
Description	Measured by the Pain Disability Index (PDI), a well-validated measure of the extent to which pain interferes with different daily activities (Range 0-70). Higher scores indicate greater interference from pain.
Time Frame	Change in score from Baseline to 16 weeks, and Baseline to 24 weeks

Outcome Measure Data

Analysis Population Description

Not all participants completed follow-up questionnaires at both follow-up time points.

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	28
16 weeks	1.11 (13.68)	-5.18 (10.50)
24 weeks	-2.83 (9.18)	-1.22 (13.65)

21. Other Pre-specified Outcome

Title	Change in Weight
Description	Measured during in-person visit at baseline and post-intervention.
Time Frame	Change from Baseline to Week 16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	26
Mean (Standard Deviation) [pounds]	-2.08 (5.68)	0.09 (4.88)

22. Other Pre-specified Outcome

Title	Change in Body Mass Index (BMI)
Description	Measured during in-person visit at baseline and post-intervention.
Time Frame	Change from Baseline to Week 16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	27	26
Mean (Standard Deviation) [kg/m^2]	-0.28 (1.11)	0.00 (0.73)

23. Other Pre-specified Outcome

Title	Change in Blood Pressure (Systolic)
Description	Measured during in-person visit at baseline and post-intervention.
Time Frame	Change from Baseline to Week 16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	27	25
Mean (Standard Deviation) [millimeters of mercury]	-5.52 (15.99)	-1.08 (17.21)

24. Other Pre-specified Outcome

Title	Change in Blood Pressure (Diastolic)
Description	Measured during in-person visit at baseline and post-intervention.
Time Frame	Change from Baseline to Week 16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	27	25
Mean (Standard Deviation) [millimeters of mercury]	-3.00 (7.76)	-0.36 (11.28)

25. Other Pre-specified Outcome

Title	Change in Hemoglobin A1c
Description	Measured during in-person visit at baseline and post-intervention.
Time Frame	Change from Baseline to Week 16

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Positive Psychology + Motivational Interviewing	Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.	Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
Measure Participants	28	26
Mean (Standard Deviation) [mg/dL]	0.10 (1.09)	0.10 (0.44)

Adverse Events

Time Frame	24 weeks
Adverse Event Reporting Description	Adverse events are "any untoward or unfavorable medical occurrence in a human subject including any abnormal sign, symptom or disease...whether or not associated with the subject's participation in the research."
Arm/Group Title	Positive Psychology + Motivational Interviewing		Diabetes Education
Arm/Group Description	Participants will complete weekly positive psychology exercises and will systematically set goals related to physical activity. Study trainers will review the positive psychology exercises on the phone each week and will use motivational interviewing techniques to facilitate goal setting. Positive Psychology + Motivational Interviewing: Participants randomized to PP-MI will receive a treatment manual. For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. Following randomization, participants will engage in weekly, 30-minute phone calls over the next 16 weeks. Participants will independently complete PP exercises and MI-based goals between phone sessions and review them during phone sessions.		Participants will speak on the telephone each week with a study trainer. During these calls, the trainer will provide education about a health behavior related to diabetes health (physical activity, medication adherence, diet). Diabetes Education: Each week, participants will learn about a different health behavior topic related to diabetes health. As an attentional control, this condition has a parallel structure to the experimental arm with a treatment manual, weekly assignments, and weekly calls to review assignments.
All Cause Mortality
	Positive Psychology + Motivational Interviewing		Diabetes Education
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/35 (0%)		0/35 (0%)
Serious Adverse Events
	Positive Psychology + Motivational Interviewing		Diabetes Education
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	4/35 (11.4%)		0/35 (0%)
Cardiac disorders
Unexpected Atrial Fibrillation	2/35 (5.7%)	2	0/35 (0%)	0
Infections and infestations
Leg infection	1/35 (2.9%)	1	0/35 (0%)	0
Respiratory, thoracic and mediastinal disorders
Unexpected acute respiratory failure	1/35 (2.9%)	1	0/35 (0%)	0
Other (Not Including Serious) Adverse Events
	Positive Psychology + Motivational Interviewing		Diabetes Education
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	12/35 (34.3%)		6/35 (17.1%)
Ear and labyrinth disorders
Unexpected ear fullness	1/35 (2.9%)	1	0/35 (0%)	0
Endocrine disorders
Unexpected hypoglycemia	1/35 (2.9%)	1	2/35 (5.7%)	4
Gastrointestinal disorders
Unexpected gastrointestinal problems	0/35 (0%)	0	1/35 (2.9%)	1
General disorders
Unexpected abdominal pain and diarrhea	0/35 (0%)	0	1/35 (2.9%)	1
Unexpected nose bleed	0/35 (0%)	0	1/35 (2.9%)	1
Unexpected dizziness and abdominal pain	0/35 (0%)	0	1/35 (2.9%)	1
Unexpected fall	3/35 (8.6%)	5	0/35 (0%)	0
Unexpected leg cramps	2/35 (5.7%)	2	0/35 (0%)	0
Unexpected kidney stone	1/35 (2.9%)	1	0/35 (0%)	0
Unexpected flank pain	1/35 (2.9%)	1	0/35 (0%)	0
Unexpected shortness of breath	1/35 (2.9%)	1	0/35 (0%)	0
Unexpected ankle injury	1/35 (2.9%)	1	0/35 (0%)	0
Unexpected episode of high blood pressure	1/35 (2.9%)	1	0/35 (0%)	0
Injury, poisoning and procedural complications
Cat bite	1/35 (2.9%)	1	0/35 (0%)	0

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT 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.