Accommodative lag by autorefraction and two dynamic retinoscopy methods.

PURPOSE

To evaluate two clinical procedures, Monocular Estimate Method (MEM) and Nott retinoscopy, for detecting accommodative lags 1.00 diopter (D) or greater in children as identified by an open-field autorefractor.

METHODS

One hundred sixty-eight children 8 to <12 years old with low myopia, normal visual acuity, and no strabismus participated as part of an ancillary study within the screening process for a randomized trial. Accommodative response to a 3.00 D demand was first assessed by MEM and Nott retinoscopy, viewing binocularly with spherocylindrical refractive error corrected, with testing order randomized and each performed by a different masked examiner. The response was then determined viewing monocularly with spherical equivalent refractive error corrected, using an open-field autorefractor, which was the gold standard used for eligibility for the clinical trial. Sensitivity and specificity for accommodative lags of 1.00 D or more were calculated for each retinoscopy method compared to the autorefractor.

RESULTS

One hundred sixteen (69%) of the 168 children had accommodative lag of 1.00 D or more by autorefraction. MEM identified 66 children identified by autorefraction for a sensitivity of 57% (95% CI = 47 to 66%) and a specificity of 63% (95% CI = 49 to 76%). Nott retinoscopy identified 35 children for a sensitivity of 30% (95% CI = 22 to 39%) and a specificity of 81% (95% CI = 67 to 90%). Analysis of receiver operating characteristic curves constructed for MEM and for Nott retinoscopy failed to reveal alternate cut points that would improve the combination of sensitivity and specificity for identifying accommodative lag > or =1.00 D as defined by autorefraction.

CONCLUSIONS

Neither MEM nor Nott retinoscopy provided adequate sensitivity and specificity to identify myopic children with accommodative lag > or =1.00 D as determined by autorefraction. A variety of methodological differences between the techniques may contribute to the modest to poor agreement.