[Analysis of anthropometry on head and eye for stipulating of children's spectacle frames].

OBJECTIVE: To investigate the normal value of six parameters of head and eye in Chinese children, including interorbit distance (IOD), interpupillary distance (IPD), superior otobasion-ectocochion distance (obs-ec), intersuperior otobasion distance (obs-obs), exophthalmos and nasal basis angle, for stipulating the sizes of children spectacle frames. METHODS: The value of these six parameters in 10 171 children ages 5 to 17 years old were measured with caliper in four cities and the results were analyzed. RESULTS: The IOD, IPD, obs-ec and obs-obs were increased and positively correlated with the age. The differences of these parameters among different ages were statistically significant (F = 0.97, P < 0.01), especially in IPD before 15, IOD before 13, obs-ec and obs-obs before 12 and exophthalmos before 12 years old. The fastest growth age in IPD, IOD, exophthalmos, obs-ec and obs-obs was 10, 11, 5, 7 and 11 years old, respectively. The growth period of IPD, IOD, exophthalmos, obs-ec and obs-obs was 5 - 15, 5 - 13, 5 - 8, 5 - 12 and 5 - 15 years old. The difference of these six parameters among children in 4 cities were statistically significant (t = 3.1, P < 0.01). CONCLUSIONS: The most active growth period of IPD, IOD, obs-obs, obs-ec and exophthalmos lies between 5-15 years old in Chinese children 5-17 years old. Although the differences of these six parameters between male and female and among children in four cities are statistically significant, practically they are not important for stipulating the sizes of children's spectacle frames.

Near-work activity, night-lights, and myopia in the Singapore-China study.

OBJECTIVE: To investigate the relationship among near-work activity, night-lights, and myopia in schoolchildren in Singapore and Xiamen, China. METHODS: The refractive error and ocular dimensions of 957 Chinese schoolchildren aged 7 to 9 years in Singapore and Xiamen, China, were determined using cycloplegic autorefraction and A-scan ultrasound biometry. Information on near-work activity (number of books read per week, reading in hours per day) and night-light use before age 2 years was obtained. RESULTS: The prevalence rate of myopia was 36.7% (95% confidence interval [CI], 33.0%-40.3%) in Singapore and 18.5% (95% CI, 14.0%-23.1%) in Xiamen, China. The crude odds ratio (OR) of higher myopia (at least -3.0 diopters) for children who read more than 2 books per week was 3.50 (95% CI, 2.15-5.70). In a multivariate logistic regression model, the OR of higher myopia for children who read more was 2.81 (95% CI, 1.69-4.69), adjusted for age, night-light use, parental myopia, and country, whereas there was no association between night-light use before age 2 years and higher myopia (OR, 1.54; 95% CI, 0.92-2.58), after controlling for age, books read per week, parental myopia, and country. MAIN OUTCOME MEASURES: The ORs of higher myopia for children who read more and children who are exposed to night-lights before age 2 years. CONCLUSIONS: Reading (number of books per week) may be associated with higher myopia in Chinese schoolchildren. However, night-light use does not seem to be related to higher myopia.