“…The results interpretation should be cautious as the 95% CIs of ORs were often overlapped. Various measures (socioeconomic factors, injuries, Table 4 Contribution of socioeconomic factors, school, behaviour and health-related difficulties to the associations between sleep difficulty and school and out-of-school single and repeated injuries (vs. none): odds ratio (OR), 95% confidence interval (CI) and contribution (% sleep difficulty, school performance, drug use, health status, psychological health, and involvement in violence) have been used in other studies (Bhattacherjee et al, 2013;Chau et al, 2008Chau et al, , 2011Hibell et al, 2004;Kandel and Davies, 1982;Leplège et al, 2000;Mayet et al, 2011;Molcho et al, 2006;Raphael et al, 2005;Skevington et al, 2004;Swanh et al, 2012). School performance and obesity were objective measures.…”