Association of adolescents’ independent mobility with road traffic injuries in Karachi, Pakistan: a cross-sectional study

OBJECTIVE: Participation in walking, cycling and taking public transportation without adult supervision is defined as independent mobility of children and adolescents. The association between adolescents’ independent mobility and road traffic injury (RTI) is unclear. The purpose of this study is to determine measures of adolescents’ independent mobility associated with RTIs in an urban lower middle-income setting. STUDY DESIGN: Cross-sectional survey. SETTING: Schools in Karachi, Pakistan. PARTICIPANTS: Adolescents aged 10–19 years in grades 6–10 were enrolled from private and public schools. OUTCOME: Any self-reported lifetime RTI sustained as a pedestrian, as a cyclist or while in a car or another vehicle that resulted in any first aid at home/school or consultation in a healthcare setting. EXPOSURE: Self-reported independent mobility was assessed by four variables. (1) Any travel companion from school to home on the survey day, (2) parental permission to cross main roads alone, (3) parental permission to travel by public bus alone and (4) activity/activities outside the home on the previous weekend alone. RESULTS: Data from 1264 adolescents, 10–19 years old, were included. Most were females (60%). Adolescents who had parental permission to cross main roads alone (adjusted OR (aOR) 1.39; 95% CI 1.04 to 1.86) and who participated in one or more activities outside the home alone on the previous weekend (aOR 2.61; 95% CI 1.42 to 5.13) or participated in a mixture of activities with and without adult accompaniment (aOR 2.50; 95% CI 1.38 to 4.89) had higher odds of RTIs. CONCLUSIONS: Parental permission to cross main roads alone and participation in activity/activities outside the home on the previous weekend alone were two measures of independent mobility associated with higher odds of RTIs among adolescents. The study provides an understanding of the risk posed by adolescents’ independent mobility in road traffic environments.