Strategies to improve the accuracy of vision measurement by teachers in rural Chinese secondary schoolchildren: Xichang Pediatric Refractive Error Study (X-PRES) report no. 6.
OBJECTIVE
To assess and improve the accuracy of lay screeners compared with vision professionals in detecting visual impairment in secondary schoolchildren in rural China.


METHODS
After brief training, 32 teachers and a team of vision professionals independently measured vision in 1892 children in Xichang. The children also underwent vision measurement by health technicians in a concurrent government screening program.


RESULTS
Of 32 teachers, 28 (87.5%) believed that teacher screening was worthwhile. Sensitivity (93.5%) and specificity (91.2%) of teachers detecting uncorrected presenting visual acuity of 20/40 or less were better than for presenting visual acuity (sensitivity, 85.2%; specificity, 84.8%). Failure of teachers to identify children owning but not wearing glasses and teacher bias toward better vision in children wearing glasses explain the worse results for initial vision. Wearing glasses was the student factor most strongly predictive of inaccurate teacher screening (P < .001). The sensitivity and specificity of the government screening program detecting low presenting visual acuity were 86.7% and 28.7%, respectively.


CONCLUSIONS
Teacher vision screening after brief training can achieve accurate results in this setting, and there is support among teachers for screening. Screening of uncorrected rather than presenting visual acuity is recommended in settings with a high prevalence of corrected and uncorrected refractive error. Low specificity in the government program renders it ineffective.
Department of Ophthalmology and Visual Science, The Chinese University of Hong Kong, Hong Kong.
Abhishek
A
Sharma
Liping
L
Li
Yue
Y
Song
Kai
K
Choi
Dennis S C
DS
Lam
Mingzhi
M
Zhang
Mingwei
M
Zheng
Zhongxia
Z
Zhou
Xiaojian
X
Liu
Bin
B
Wu
Nathan
N
Congdon
D000293:Adolescent; D017677:Age Distribution; D002648:Child; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D016001:Confidence Intervals; D005139:Eyeglasses / Q000706:statistics & numerical data; D005178:Faculty; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D011336:Probability; D012424:Rural Population; D012572:School Health Services; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D013334:Students / Q000706:statistics & numerical data; D014786:Vision Disorders / Q000175:diagnosis* / Q000453:epidemiology; D015351:Vision Screening / Q000379:methods*; D014787:Vision Tests / Q000379:methods*