两种视力检查方法应用于低年级小学生筛查性近视研究

作者: 梁莉;许韶君;朱懿;徐星;赵梦雅;温跃春;陶芳标;

期刊: 中国学校卫生

DOI：10.16835/j.cnki.1000-9817.2024063

摘要

目的 探讨两种视标通过标准检查裸眼视力(UCVA)方法界定低年级小学生视力不良,及其联合非睫状肌麻痹状态下电脑验光(NCAR)界定筛查性近视率的差异,并以睫状肌麻痹电脑验光(CAR)作为金标准评价其真实性和可靠性,为规范UCVA检查方法提供科学依据。

方法 2023年3月22日—4月9日,采用方便整群抽样方法选取合肥市某小学549名一和二年级学生(7～8岁),分别采用每行视标不能认错一半(V1)和4.0～4.5,4.6～5.0,5.1～5.3各行视标每行分别不能认错1,2,3个(V2)两种方法检查UCVA,并进行NCAR,其中187名完成CAR检查。采用配对Wilcoxon秩和检验和McNemar检验比较V1和V2方法视力检查结果及其界定视力不良和筛查性近视率的组间差异;以CAR为金标准,评价V1和V2方法联合NCAR界定筛查性近视的真实性和可靠性。

结果 V1与V2左右眼视力UCVA检查结果[右:5.0(4.9,5.0),4.9(4.8,5.0);左:5.0(4.9,5.0),4.9(4.8,5.0)]差异均有统计学意义(Z右眼=-13.95,Z左眼=-13.34,P值均<0.01)。V1与V2方法右眼视力不良检出率分别为43.53%和63.21%,左眼分别为44.08%和62.11%,差异均有统计学意义(χ右眼2=106.1,χ左眼2=95.09,P值均<0.01)。联合NCAR右眼筛查性近视率分别为21.49%和24.59%,左眼分别为21.31%和23.13%,差异均有统计学意义(χ右眼2=15.06,χ左眼2=8.10,P值均<0.01)。以CAR为金标准的右眼和左眼近视检出率分别为16.58%和17.11%;V1和V2两种方法界定筛查性近视右眼约登指数分别为0.80和0.79,左眼分别为0.85和0.83;右眼一致率分别为91.98%和89.30%,左眼分别为94.12%和91.98%;右眼Kappa值分别为0.73和0.67,左眼分别为0.81和0.75。

结论 两种UCVA方法联合NCAR界定筛查性近视的真实性和可靠性V1均高于V2。视力检查方法的视标通过标准建议统一为辨认正确的视标数应超过该行视标总数的一半。

Abstract 

Objective To explore two visual acuity standards for examining uncorrected visual acuity (UCVA) to define poor vision in lower-grade elementary school students, and to compare the difference of screening myopia rates when combined with noncycloplegic auto-refraction ( NCAR), so as to provide a scientific basis for standardizing UCVA examination methods using CAR as the gold standard of authenticity and reliability.

Methods From March 22nd to April 9th, 2023, a total of 549 first and second.grade students aged 7-8 years from a primary school in Hefei City were selected for the study by convenient cluster sampling method. Two methods were employed for UCVA examination: the first method involved charts where the student could not make mistakes in identifying at least half of the characters per line (V1), and the second method used charts with character sizes ranging from 4.0-4.5, 4.6-5.0 and 5.1-5.3, without allowing 1, 2 and 3 errors per line ( V2). While NCAR was performed, then 187 students underwent CAR examination. Paired Wilcoxon rank-sum test and McNemar test were used to compare the differences between V1 andV2 methods in defining poor vision and screening myopia rates. Using CAR as the gold standard, the authenticity and reliability of defining screening myopia rates through the combination of V1 and V2 methods along with NCAR were evaluated.

Results The UCVA examination results for V1 and V2 showed statistically significant differences in both the right eye [5.0(4.9, 5.0), 4.9(4.8, 5.0)] and the left eye [5.0(4.9, 5.0), 4.9(4.8, 5.0)](Z=-13.95, -13.34, P<0.01). The detection rates of poor vision for the right eye were 43.53% for V1 and 63.21% for V2, and the left eye with 44.08% for V1 and 62.11% for V2, with statistically significant differences (X²= 106.01, 95.09, P<0.01). When screening myopia rates were assessed for UCNA methods combined with NCAR, the right eye rates were 21.49% for V1 and 24.59% for V2, and the left eye rates were 21.31% for V1 and 23.13% for V2, with statistically significant differences (X²= 15.06, 8.10, P<0.01). Using CAR as the gold standard, the detection rates in the right eye and left eye were 16.58% and 17.11%, respectively. The Youden indices for defining screening myopia in the right eye were 0.80 for V1 and 0.79 for V2, and the left eye with 0.85 for V1 and 0.83 for V2. The agreement rates for the right eye were 91.98% for V1 and 89.30% for V2, and the left eye with 94.12% for V1 and 91.98% for V2. The Kappa values for the right eye were 0.73 for V1 and 0.67 for V2, and the left eye with 0.81 for V1 and 0.75 for V2.

Conclusions Authenticity and reliability of two UCVA examination methods combined with NCAR in defining screening myopia are higher in V1 than V2 methods. It is recommended to unify the visual acuity examination methods by requiring the correct identification of more than half of the total number of visual markers in a row.

Keywords Optometry; Myopia; Multiphasic screening; Reference standards; Students