Refractive Accuracy of "2WIN" and Portable Autorefractors

Alaska Blind Child Discovery (Other)
Overall Status
Completed ID

Study Details

Study Description

Brief Summary

Youth and some adults have photoscreening refractions and hand-held auto refraction before cycloplegia refraction during new and follow up eye examinations. Vector math is applied to each refraction to determine how closely the hand-held "dry" devices match actual refraction.

Condition or Disease Intervention/Treatment Phase
  • Device: "2WIN" Photoscreener
  • Device: "Plusoptix A12"
  • Device: "Retinomax"

Detailed Description

A closeness-of-fit algorithm utilizing vector transformations of astigmatism is designed and applied to 50-years of clinical international refractive experience.

As a part of new and follow up comprehensive eye examinations, patients and parents consented to confirm the cycloplegic refraction to other portable refractive tools.

The ability of photoscreeners "2WIN" ("Adaptica," Padova italy), "PlusoptiX A12" (Nuremberg, Germany) and "Retinomax" (Righton, Tokyo, Japan) to match actual refraction is assessed utilizing the new algorithm.

This algorithm could then be applied to batches of donated spectacles distend by charitable organizations worldwide if portable auto refracting devices are employed.

Study Design

Study Type:
Actual Enrollment :
708 participants
Observational Model:
Time Perspective:
Official Title:
The Refractive Accuracy of Photoscreeners "2WIN" and "PlusoptiX" and the "Retinomax" Auto Refractor
Actual Study Start Date :
Jan 9, 2020
Actual Primary Completion Date :
Apr 1, 2021
Actual Study Completion Date :
Apr 1, 2021

Outcome Measures

Primary Outcome Measures

  1. Refractive Accuracy [1 day]

    spherical equivalent

  2. Refractive Accuracy [1 day]

    Vector transform J0 and J45 astigmatism

  3. Refractive Accuracy [1 day]

    Spectacle comparison score (Percent similarity combined sphere-cylinder)

Secondary Outcome Measures

  1. Impact of age [1 day]

    Spectacle similarity score striated by age relative to patient's ability to accommodate

Eligibility Criteria


Ages Eligible for Study:
6 Months to 95 Years
Sexes Eligible for Study:
Accepts Healthy Volunteers:
Inclusion Criteria:
  • Patient undergoing new or follow examination at pediatric eye and adult strabismus clinic Willing to undergo screening refractive device developmental delays included
Exclusion Criteria:
  • Intraocular lens in place

Contacts and Locations


Site City State Country Postal Code
1 Alaska Children's EYE & Strabismus Anchorage Alaska United States 99508

Sponsors and Collaborators

  • Alaska Blind Child Discovery


  • Principal Investigator: Bob Arnold, MD, Coordinator Alaska Blind Child Discovery

Study Documents (Full-Text)

None provided.

More Information


Responsible Party:
Alaska Blind Child Discovery Identifier:
Other Study ID Numbers:
  • ABCD RefAcc
First Posted:
Jan 31, 2020
Last Update Posted:
Jul 23, 2021
Last Verified:
Jul 1, 2020
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD:
Studies a U.S. FDA-regulated Drug Product:
Studies a U.S. FDA-regulated Device Product:
Keywords provided by Alaska Blind Child Discovery
Additional relevant MeSH terms:

Study Results

No Results Posted as of Jul 23, 2021