Optometry & Vision Science

Skip Navigation LinksHome > July 2011 - Volume 88 - Issue 7 > Comparison of the Retinomax and Palm-AR Auto-Refractors: A P...
Optometry & Vision Science:
doi: 10.1097/OPX.0b013e3182192658
Original Article

Comparison of the Retinomax and Palm-AR Auto-Refractors: A Pilot Study

The Vision in Preschoolers (VIP) Study Group

Collapse Box


Purpose. To compare the performance of two handheld auto-refractors, the Retinomax and the Palm-Automatic Refractometer (Palm-AR), for detecting significant vision disorders in pre-school children.

Methods. Children attending Philadelphia PreKindergarten Head Start were screened with the Retinomax and Palm-AR and underwent a gold standard eye examination. The results of cycloplegic retinoscopy, cover testing, and visual acuity were used to classify children as having normal vision or one of four conditions: amblyopia, strabismus, significant refractive error, and reduced visual acuity. Pass/fail criteria for each instrument were selected to maximize overall sensitivity (with specificity set at 90% and at 94%) for detecting targeted disorders. Comparisons of sensitivities between the auto-refractors were performed using the exact McNemar test.

Results. Testability was >99% for both instruments. Test time was similar for the two instruments (median 2 min; p = 0.10). At 90% specificity, the sensitivity for detection of one or more targeted conditions was 74% for the Palm-AR and 78% for the Retinomax. At 94% specificity, the sensitivity for detection of one or more targeted conditions was 66% for both the Palm-AR and the Retinomax. At 90% specificity, the sensitivity for detecting significant refractive error was 84% for both auto-refractors, and at 94% specificity, the sensitivity was 76% for the Palm AR and 75% for the Retinomax. There were high correlations between the instruments for sphere (r = 0.85) and cylinder (r = 0.88) power. The mean difference between instruments was −0.13 diopters (D) (95% limit of agreement: −2.28 to 2.02) for sphere, and −0.15 D (95% limit of agreement: −0.89 to 0.59) for cylinder.

Conclusions. In this pilot study, the Retinomax and Palm-AR appear comparable with respect to testability, sensitivity, and specificity. There was strong agreement in readings of sphere and cylinder indicating that they may perform similarly in a screening setting.

© 2011 American Academy of Optometry


Article Tools


Article Level Metrics

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.