International Business School, Shaanxi Normal University, Shaanxi, China.
Center for Experimental Economics in Education, Shaanxi Normal University, Shaanxi, China.
Acta Ophthalmol. 2019 May;97(3):e419-e425. doi: 10.1111/aos.13954. Epub 2018 Oct 21.
To explore the accuracy and cost-effectiveness of three vision screening models among preschool children in rural China.
Vision screening was carried out among children aged 4-5 years in 65 preschools in two counties in Northwest China, using Crowded Single Lea Symbols to test visual acuity. Children were assigned randomly by school to one of three screening models: screening by teachers (15 schools, 1835 children), local optometrists (30 schools, 1718 children) or volunteers (20 schools, 2183 children). Children identifying ≥2 symbols incorrectly in either eye failed screening. Accuracy of screening was compared with screenings executed by experienced optometrists among 141 children selected randomly from the three screening models. Direct and indirect costs for each model were assessed. Costs to detect a true case failed screening were estimated.
The sensitivity for three models ranged from 76.9% to 87.5%, specificity from 84.9% to 86.7% and standardized positive predictive value from 83.7% to 85.7%. None differed significantly between models. The costs per case detected were $37.53, $59.14 and $52.19 for the teachers, local optometrists and volunteers. In producing the cost estimates for teacher screening and local optometrist screening models, we used a salary payment that was identical for both models (with the salary being equal to that of the optometrist). The teacher screening model was the most cost-effective.
Accuracy of screening by teachers, local optometrists and volunteers was the same in this setting, but the use of teachers was most cost-effective, reducing the cost per case detected by almost 40%.
探索三种视力筛查模型在中国农村学龄前儿童中的准确性和成本效益。
在中国西北地区的两个县的 65 所幼儿园中，使用拥挤单 Lea 符号对 4-5 岁儿童进行视力筛查。按学校将儿童随机分配到三种筛查模式之一：教师筛查（15 所学校，1835 名儿童）、当地验光师（30 所学校，1718 名儿童）或志愿者（20 所学校，2183 名儿童）。双眼识别≥2 个符号错误的儿童筛查失败。通过从三种筛查模式中随机选择的 141 名儿童，比较了筛查的准确性与经验丰富的验光师的筛查。评估了每种模式的直接和间接成本。估计了每个模型检测到一个真实病例的漏诊成本。
三种模型的灵敏度为 76.9%至 87.5%，特异性为 84.9%至 86.7%，标准化阳性预测值为 83.7%至 85.7%。模型之间无显著差异。每个病例的检测成本分别为教师、当地验光师和志愿者筛查模式的 37.53 美元、59.14 美元和 52.19 美元。在编制教师筛查和当地验光师筛查模型的成本估算时，我们使用了两种模式相同的工资支付（工资与验光师相同）。教师筛查模式最具成本效益。
在这种情况下，教师、当地验光师和志愿者的筛查准确性相同，但使用教师的成本效益最高，将每个检测病例的成本降低了近 40%。
