Hashemi Hassan, Pakzad Reza, Yekta Abbasali, Asharlous Amir, Aghamirsalim Mohammadreza, Ostadimoghaddam Hadi, Valadkhan Mehrnaz, Khabazkhoob Mehdi
Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran.
Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran.
Saudi J Ophthalmol. 2019 Apr-Jun;33(2):148-152. doi: 10.1016/j.sjopt.2019.02.009. Epub 2019 May 4.
To determine the distribution of near point of convergence (NPC) according to age, sex, and refractive error in a rural population above 1 year of age in 2015.
In this population-based cross-sectional study, multistage cluster sampling was applied to randomly select two underserved areas from the north and southwest of Iran and all individuals above 1 year living in these areas were invited to participate in the study. All participants underwent ocular examinations including visual acuity measurement, refraction, binocular vision testing including cover test and measurement of NPC, and slit lamp biomicroscopy.
Of 3851 who were invited, 3314 participated in the study (response rate: 86.5%). The NPC was 8.42 ± 2.94 cm in the whole population, 8.59 ± 3.07 cm in men, and 8.30 ± 2.84 cm in women. Subjects above 70 years of age had the most remote NPC (mean: 10.44 ± 3.07 cm). The mean NPC was 7.79 ± 2.93, 8.83 ± 2.72, and 9.63 ± 2.70 cm in emmetropic, myopic, and hyperopic participants, respectively. According to the results of a multiple linear regression model, NPC had a positive correlation with age (b: 0.058, < 0.001), male sex (b: 0.336, : 0.005), and hyperopia (b: 0.044, : 0.011). Among the evaluated variables, age had the greatest effect on NPC (Standardized coefficient: 0.402).
The distribution of NPC in the Iranian population is different from other populations. Since NPC is influenced by age more than any other variable and presented normal values according to age in this study, the results can be used to interpret clinical measurements for diagnosis and treatment purposes.
确定2015年1岁以上农村人口中近点集合（NPC）根据年龄、性别和屈光不正的分布情况。
在这项基于人群的横断面研究中，采用多阶段整群抽样方法从伊朗北部和西南部随机选择两个服务不足的地区，并邀请居住在这些地区的所有1岁以上个体参与研究。所有参与者均接受眼科检查，包括视力测量、验光、双眼视觉测试（包括遮盖试验和NPC测量）以及裂隙灯生物显微镜检查。
在3851名被邀请者中，3314人参与了研究（应答率：86.5%）。整个人群的NPC为8.42±2.94厘米，男性为8.59±3.07厘米，女性为8.30±2.84厘米。70岁以上的受试者NPC最远（平均值：10.44±3.07厘米）。正视、近视和远视参与者的平均NPC分别为7.79±2.93、8.83±2.72和9.63±2.70厘米。根据多元线性回归模型的结果，NPC与年龄呈正相关（b：0.058，P<0.001）、男性（b：0.336，P：0.005）和远视（b：0.044，P：0.011）。在评估的变量中，年龄对NPC的影响最大（标准化系数：0.402）。
伊朗人群中NPC的分布与其他人群不同。由于NPC受年龄影响大于任何其他变量，且在本研究中根据年龄呈现出正常值，因此这些结果可用于解释临床测量结果以进行诊断和治疗。
