The prevalence of refractive error and visual impairment among New Zealand children in a community with significant socioeconomic disadvantage: is current preschool vision screening effective?

Aim: To examine the prevalence of refractive error and visual impairment and evaluate the efficacy of B4 School Check (B4SC) vision screening, in a cohort of predominantly New Zealand Māori and Pacific children from a community with socioeconomic disadvantage.

Method: A cross-sectional investigation of children in the Welcome-to-School study. Participants received a comprehensive eye examination at six to seven years of age. Refractive error and amblyopia were identified and compared with B4SC vision screening results.

Results: One-hundred and fourteen children were assessed: 21.9% Māori, 57.9% Pacific and 20.2% Other. Over 30% of children had significant refractive error. Eighty-nine percent received a B4SC; 26.3% of children who passed the B4SC had significant refractive error. Seven children (6.1%) had amblyopia risk factors: none passed the B4SC, four were referred, one was identified for rescreening and two were not screened.

Conclusion: Refractive errors were common in this cohort. For those screened, the B4SC was effective at identifying children with amblyopia risk factors but poor at detecting refractive errors potentially affecting academic performance. The efficacy of the programme was limited by the number of children screened, inequity of screening and the mismatch between the aims of the vision screening test and the overall rationale for the B4SC.