Résumé : | SIGNIFICANCE: Wearable sensors provide the opportunity for continuous objective measurement of the visual environment with high resolution. Our findings show that absolute and temporal properties of near viewing and time
outdoors vary between myopic and nonmyopic schoolchildren, which are important considerations when studying
refractive error pathogenesis.
PURPOSE: Numerous behavioral factors, including near work, time outdoors, electronic device use, and sleep,
have been linked to myopia. The purpose of this study was to assess behaviors using subjective and objective
methods in myopic and nonmyopic schoolchildren in the United States.
METHODS: Forty children (aged 14.6 ± 0.4 years) simultaneously wore two sensors for 1 week, a Clouclip for objective measurement of near viewing and light exposure and an Actiwatch for objective measurement of activity and
sleep. Parents completed an activity questionnaire for their child. Near-viewing distance, daily duration, shortduration (>1 minute) and long-duration (>30 minutes) near-viewing episodes, light exposure, time outdoors, electronic device use, and sleep duration were analyzed by refractive error group and day of the week.
RESULTS: Objectively measured daily near-viewing duration was 6.9 ± 0.3 hours. Myopes spent more time in
near + intermediate viewing than nonmyopes ( P = .008) and had higher diopter hours ( P = .03). Short- and
long-duration near-viewing episodes were similar between groups ( P < .05 for both). Daily light exposure and time
outdoors were significantly lower for myopes ( P < .05 for both). Electronic device use (12.0 ± 0.7 hours per day)
and sleep duration (8.2 ± 0.2 hours per night) were similar between groups ( P > .05 for both).
CONCLUSIONS: Objective and subjective measures confirm that myopic and nonmyopic schoolchildren exhibit
different behaviors. Combining wearable sensors with questionnaires provides a comprehensive description of
children's visual environment to better understand factors that contribute to myopia. |