Alternative vision testing strategies not cost-effective compared to primary care screening

Universal school screening and optometric examinations for amblyopia does not show greater benefits than primary care screening, according to a recent study.

Amblyopia, also known as lazy eye, is present in 3% to 5% of young children. Conditions which increase the risk of amblyopia are seen in about 10% of children aged 3 to 6 years. To prevent lifelong vision impairment, early identification and treatment of risk factors is recommended.

Early detection of amblyopia can occur through vision screening from primary care physicians and eye care professionals, which should take place in childhood. According to the Canadian Pediatric Society, children should receive a vision screening from a primary care physician when aged 3 months, 6 months, 9 months, 1 year, and annually when aged 3 to 6 years.

Because of poor uptake of vision service in Ontario, the province adopted administering screening guidelines in senior kindergartens. However, there is little data on the benefits and cost-effectiveness of alternate vision testing strategies such as this.

To analyze the public health benefits and cost-effectiveness of amblyopia screening and optometric examinations in schools, investigators conducted an economic evaluation. Two alternative universal vision testing strategies were compared with standard primary care screening, with a simulated cohort of 25,000 children used in the comparison.

For the analysis, an assumption was made that if children were not diagnosed by an optometrist, then they had irreversible damage to their vision.

The first alternative testing strategy was the implementation of vision screening programs in schools universally. Contracted screeners trained by a public health nurse would perform the screening, and children with positive or inconclusive results were referred to an optometrist.

The second alternative testing strategy was to make optometric examinations in clinics required for all children aged between 4 and 5 years. Children would undergo a single examination.

Quality-adjusted life-years (QALYs) was the primary outcome of the study, measured by multiplying utility weights by the duration of time spent in a health state, summed over the time horizon. In each vison testing strategy, direct costs to the Ontario government were calculated.

School screening and optometric examination strategies were often more cost effective than primary care screening. The average savings per child in CAD was $84.09 for school screening and $74.47 for optometric examinations. The greatest improvement in QALYs was seen in optometric examinations, with mean QALYs of 0.0508 per child.

In a sensitivity analysis, these effects did not significantly change the threshold. Low amblyopia prevalence among children made primary care screening the preferred option for detection and treatment. This indicated that school screening and optometric examination strategies are not cost-effective relative to primary care screening.

Reference

Asare AO, Maurer D, Wong AMF, Saunders N, Ungar WJ. Cost-effectiveness of universal school- and community-based vision testing strategies to detect amblyopia in children in Ontario, Canada. JAMA Netw Open. 2023;6(1):e2249384. doi:10.1001/jamanetworkopen.2022.49384