Positive predictive value of dual-modality vision screening in school children 4-7 years of age—a retrospective review in Queensland, Australia

Abstract

To report the outcomes and positive predictive value (PPV) of vision screening in schoolchildren 4-7 years of age through the Primary School Nurse Health Readiness Program (PSNHRP) in Queensland, Australia. A retrospective review of schoolchildren who underwent vision screening between January 2017 and December 2020 was conducted. Vision screening was performed through a dual-examination method, using the Parr 4m letter-matching vision test with crowding bars and the Spot photoscreener. Children were referred to an optometrist or ophthalmologist for review as required and if they failed either screening modality. PPVs were calculated based on whether a visual abnormality was confirmed by an ophthalmologist or optometrist. Of 185,685 eligible children, 176,164 (94.9%) consented to vision screening, 164,890 (93.6%) consented children underwent vision screening, and of those 12,148 (7.4%) were referred for an eye assessment. Of the 8,659 children with a known outcome (71.3% of referred), 6,011 (69.4% of known outcomes) had a confirmed visual abnormality and 2,648 (30.6%) children did not. The PPV was 0.73 when a referral was indicated by the photoscreener result, 0.76 when indicated by visual acuity testing, and 0.91 when indicated by both the photoscreener and visual acuity testing. The PSNHRP vision screening program showed a high uptake, and the dual screening method was effective in identifying visual abnormalities, with higher PPV when both visual acuity and photoscreener results indicated a need for referral.