Pediatric Amblyopia Risk Investigation Study (PARIS)

Purpose To assess the learning curve, testability, and reliability of vision screening modalities administered by pediatric health extenders. Design Prospective masked clinical trial. Methods Two hundred subjects aged 3 to 6 underwent timed screening for amblyopia by physician extenders, including LEA visual acuity (LEA), stereopsis (RDE), and noncycloplegic autorefraction (NCAR). Patients returned for a comprehensive diagnostic eye examination performed by an ophthalmologist or optometrist. Results Average screening time was 5.4 ± 1.6 minutes (LEA), 1.9 ± 0.9 minutes (RDE), and 1.7 ± 1.0 minutes (NCAR). Test time for NCAR and RDE fell by 40% during the study period. Overall testability was 92% (LEA), 96% (RDE), and 94% (NCAR). Testability among 3-year-olds was 73% (LEA), 96% (RDE), and 89% (NCAR). Reliability of LEA was moderate ( r = .59). Reliability of NCAR was high for astigmatism (Cyl) ( r = .89), moderate for spherical equivalent (SE) ( r = .66), and low for anisometropia (ANISO) ( r = .38). Correlation of cycloplegic autorefraction (CAR) with gold standard cycloplegic retinoscopic refraction (CRR) was very high for SE (.85), CYL (.77), and moderate for ANISO (.48). Conclusions With NCAR, physician extenders can quickly and reliably detect astigmatism and spherical refractive error in one-third the time it takes to obtain visual acuity. LEA has a lower initial cost, but is time consuming, moderately reliable, and more difficult for 3-year-olds. Shorter examination time and higher reliability may make NCAR a more efficient screening tool for refractive amblyopia in younger children. Future study is needed to determine the sensitivity and specificity of NCAR and other screening methods in detecting amblyopia and amblyopia risk factors.