调研拉萨地区非近视儿童远视储备量不足现状及影响因素，为儿童屈光状态调查、近视的预防和控制提供依据。

采用随机整群抽样的方法，于2019年10月随机抽取拉萨地区一年级儿童共1853人(3706只眼)进行研究。其中，男性981人(1962只眼)，女性872人(1744只眼)。年龄6～10岁，平均(6.82±0.46)岁。按睫状肌麻痹后等效球镜屈光度(SE)<0.75 D且>－0.50 D和SE值≥0.75 D分为远视储备量不足组和远视储备量足组。通过家长问卷和眼科检查，收集一年级儿童基本人口学特征、父母屈光不正病史、用眼时间、用眼习惯、远近视力和散瞳验光等检查结果。年龄、身高、体重和SE值等符合正态分布，用( ±s)描述，组间比较采用独立样本t检验。性别、民族、父母近视个数和远视储备量不足的影响因素采用例数和百分比描述，组间比较采用χ²检验。进一步采用logistic回归分析的方法筛选儿童远视储备量不足的危险因素。

纳入本研究的拉萨地区一年级儿童全部1853人(3706只眼)睫状肌麻痹后SE平均为(1.07±0.92)D，非近视儿童有1780人(3560只眼))。其中，远视储备量不足者有377人(754只眼)，占21.18%。调查的非近视儿童中父母一方或双方都近视者有269人(538只眼)，占15.36%。连续近距离用眼超过45 min的儿童有338人(676只眼)，占19.75%；使用电子设备距离小于50 cm的儿童有732人(1464只眼)，占68.80%；看电视距离小于3 m的儿童有1170人(2340只眼)，占77.59%；有歪头写字习惯的儿童有823人(1646只眼)，占43.13%；晚上有开灯睡觉习惯的儿童有72人(144只眼)，占4.21%。远视储备量不足者男生和女生分别有942人(1884只眼)和有838人(1676只眼)，分别占23.25%和18.85%；男生高于女生，差异具有统计学意义(χ²＝5.13，P<0.05)。远视储备量不足儿童的父母一方近视、双方均近视及父母双方均不近视者分别有23人(46只眼)、54人(108只眼)及296人(592只眼)，分别占27.00%、33.33%及19.96%；父母一方近视、双方都近视者高于父母双方均不近视组者，差异具有统计学意义(χ²＝5.30，7.22; P<0.05)。有歪头写字习惯的儿童远视储备量不足者和习惯良好的儿童分别有333人(666只眼)和有243人(486只眼)，分别占40.46%和35.17%，有歪头写字习惯儿童多于习惯良好者，差异具有统计学意义(χ²＝4.04，P<0.05))。多因素logistic回归分析筛选出4项指标为儿童远视储备不足的危险因素。其中，男生(OR＝1.32，95%CI：1.04～1.67；P<0.05)，父母只有一方近视者(OR＝1.54，95%CI：1.02～2.16；P<0.05)、父母两个都是近视者(OR＝1.85，95%CI：1.13～3.05；P<0.05)和歪头写字习惯(OR＝1.30，95%CI：1.02～1.66；P<0.05)是儿童远视储备量不足的危险因素。

拉萨地区一年级儿童远视储备量不足率超过20%，用眼卫生习惯有待改善，性别、父母近视和不良用眼习惯是儿童影响远视储备量不足的危险因素。

To investigate the status and influencing factors of hyperopia reserve deficiency in non myopia children in Lhasa, which to provide the basis for the investigation of children′s refractive status and the prevention and control of myopia.

A total of 1853 first grade children (3706 eyes) in Lhasa were randomly selected in October 2019 by random cluster sampling method. There were 981 males (1962 eyes) and 872 females (1744 eyes) with the average age of (6.82±0.46) years (ranging from 6 to 10 years). According to the equivalent spherical diopter (SE) <0.75 D and >-0.50 D and SE value ≥0.75 D after cycloplegia, the children were divided into hyperopia reserve insufficient group and hyperopia reserve sufficient group. The basic demographic characteristics, parents′ history of ametroia, eye use time, eye use habits, near and far visual acuity and mydriatic refraction of first grade children were collected through parents′ questionnaire and ophthalmic examination. Age, height, weight and SE value were in accordance with normal distribution, and were described by (±s) and compared by independent sample t test between groups. The influencing factors of gender, nationality, number of parents with myopia and insufficient hyperopia reserve were described by the number of cases and percentage, and compared by χ² test between groups. Logistic regression analysis was further used to screen the risk factors of children′s hyperopia reserve deficiency.

The average SE of 1853 children (3706 eyes) in Lhasa after cycloplegia was (1.07±0.92) D, 1780 children (3560 eyes) without myopia and 377 children (754 eyes) with insufficient hyperopia reserve, accounting for 21.18%. A total of 269 children (538 eyes) with one or both parents were myopic, accounting for 15.36%. A total of 338 children (676 eyes) used their eyes for more than 45 minutes, accounting for 19.75%. There were 732 children (1464 eyes) using electronic devices with a distance of less than 50 cm, accounting for 68.80%; 1170 children (2340 eyes) watched TV less than 3 meters, accounting for 77.59%. A total of 823 children (1646 eyes) had the habit of writing with crooked head, accounting for 43.13%. A total of 72 children (144 eyes) had the habit of turning on the lights at night, accounting for 4.21%. There were 942 boys (1884 eyes) and 838 girls (1676 eyes) with insufficient hyperopia reserve, accounting for 23.25% and 18.85% respectively, and the former was more than the latter, and the difference was statistically significant (χ²=-5.13, P<0.05). There were 23 cases (46 eyes), 54 cases (108 eyes) and 296 cases (592 eyes) with one or both parents′ myopia, accounting for 27.00%, 33.33% and 19.96% respectively. The myopia of one or both parents was significantly higher than that of both parents without myopia (χ²=5.30, 7.22; P<0.05). A total of 333 children (666 eyes) with insufficient hyperopia reserve and 243 children (486 eyes) with good habit of writing with crooked head accounted for 40.46% and 35.17%, respectively. Children with crooked head writing habit were more than those with good habit, and the difference was statistically significant (χ²=4.04, P<0.05). Multivariate logistic regression analysis showed that 4 risk factors of children′s hyperopia reserve insufficiency. Among them, boys (OR=1.32, 95%CI: 1.04 to 1.67; P<0.05), parents with only one myopia (OR=1.54, 95%CI: 1.02 to 2.16; P<0.05), parents with both myopia (OR=1.85, 95%CI: 1.13 to 3.05, P<0.05) and crooked head writing habits (OR=1.30, 95%CI: 1.02 to 1.66; P<0.05) was a risk factor for children with insufficient hyperopia reserve.

The rate of insufficient foresight reserves among first grade children in Lhasa exceeds 20%, and their eye hygiene habits need to be improved. Gender, parental myopia, and poor eye habits are risk factors for children′ s insufficient foresight reserves.