Baseline characteristics in the Israel refraction, environment, and devices (iREAD) study

Abstract

The purpose of this study is to present baseline data from a longitudinal study assessing behavioral factors in three groups of boys in Israel with varying myopia prevalence. Ultra-Orthodox (N = 57), religious (N = 67), and secular (N = 44) Jewish boys (age 8.6 ± 1.4 years) underwent cycloplegic autorefraction and axial-length measurement. Time-outdoors and physical-activity were assessed objectively using an Actiwatch. Ocular history, educational factors, and near-work were assessed with a questionnaire. Group effects were tested and mixed effects logistic and linear regression were used to evaluate behaviors and their relationship to myopia. The prevalence of myopia (≤ - 0.50D) varied by group (ultra-Orthodox: 46%, religious: 25%, secular: 20%, P < 0.021). Refraction was more myopic in the ultra-Orthodox group (P = 0.001). Ultra-Orthodox boys learned to read at a younger age (P < 0.001), spent more hours in school (P < 0.001), spent less time using electronic devices (P < 0.001), and on weekdays, spent less time outdoors (P = 0.02). Increased hours in school (OR 1.70) and near-work (OR 1.22), increased the odds of myopia. Being ultra-Orthodox (P < 0.05) and increased near-work (P = 0.007) were associated with a more negative refraction. Several factors were associated with the prevalence and degree of myopia in young boys in Israel, including being ultra-Orthodox, learning to read at a younger age, and spending more hours in school.

Figure 1

Protocol, recruitment, and enrollment for the 18-month iREAD study. Baseline analysis (N = 168) is presented in this paper. *11 boys were excluded: 3 had less than 6/9 acuity, 1 had less than 6/9 acuity and high astigmatism, 4 had high hyperopia, 3 had high astigmatism. ^†5 boys were excluded: 4 provided less than 4 days of valid Actiwatch data and 1 did not fill out the questionnaire.

Figure 2

Environmental and behavioral measures. Mean ± standard deviation daily (A) time outdoors (hours), (B) light exposure (lux), (C) activity (counts per 15 s), (D) near work (hours), (E) electronic device use (hours), and (F) television (hours), are shown for weekdays, Shabbat, and the whole week (overall) for ultra-Orthodox (filled bars), religious (gray bars), and secular (open bars) children; P < 0.05, **P < 0.01, ***P < 0.001 for Bonferroni-corrected post hoc pairwise comparisons.

Figure 3

Activity in counts per 15 s (CP15) and light exposure (lux) analyzed by hour. Activity in counts per 15 s (CP15) and light exposure (lux) analyzed by hour for weekdays (A,C) and Shabbat (B,D) for ultra-Orthodox (UO, triangles), religious (R, squares), and secular (S, circles) groups; error bars represent 95% confidence intervals; post-hoc pairwise comparisons P < 0.05: *UO < S, ^†UO < R, ^‡R < S, ^¥S < R, ^#S < UO, ^§R < UO.