Purpose:
To determine success rates and examine confidence ratings of the SureSight (SS, Welch Allyn) Autorefractor, as a function of age, in assessment of refractive error in infants and young children from a Native American population with a high prevalence of astigmatism.
Methods:
Subjects were 956 children, aged 6 months to 8 years, recruited through Women, Infants and Children (WIC) clinics, the Head Start Program, and K and 1st grade elementary school classrooms on the Tohono O’odham Reservation between 2005 and 2007. Three non-cycloplegic right-eye SS (child mode) measurements were attempted on each child. Results were grouped by age: 6 months to <1 year, 1 to <2 years, 2 to <3 years, 3 to <4 years, 4 to <5 years, 5 to <6 years, 6 to <7 years and 7 to <8 years. Confidence ratings were categorized as <6 or ≥ 6 (the confidence rating recommended by the manufacturer).
Results:
On average, 2.7 measurements were obtained for each child and this number did not vary by age. No measurement could be obtained for 5% of subjects. The proportion of children for whom the confidence rating on the first measurement was ≥ 6 ranged from 53.6% at 6 months to <1 year to 90% at 6 to <7 years and varied significantly by age group (graph). Confidence ratings ≥ 6 on at least one of a maximum of 3 readings ranged from 76.8% at 6 months to <1 year to 97.5% at 6 to <7 years and varied significantly by age group (graph). Allowing 3 measurements significantly improved the probability of obtaining a rating ≥ 6 in all age groups except 6 to < 7 years (ps < 0.05).
Conclusions:
SS success rate in obtaining at least 1 measurement was high across all age groups. Allowing 3 measurements significantly increased the likelihood of obtaining a rating ≥ 6.
Keywords: infant vision • refractive error development • detection