Association of age and severe injury in young motorcycle riders: A cross-sectional study from Karachi, Pakistan.

Introduction: The burden imposed by motorcyclist deaths and injuries is high in low- and middle-income countries. Many injured motorcycle riders in these settings are underage. The aim of this study was to assess the association between age and severe injury in young motorcycle riders.

Methods: We analysed road traffic injury surveillance data from the emergency rooms of five hospitals in Karachi from 2007 to 2015. We used logistic regression to assess the association of motorcycle riders' age, categorised as underage (13-17 years), early licensing age (18-19 years) and late licensing age (20-24 years), with severe injury, defined as an Injury Severity Score (ISS) ≥ 16.

Results: The study sample included 45,366 motorcycle riders. There were 10115 (22.3%) motorcycle riders aged 13-17 years, 9899 (21.8%) aged 18-19 years and 25352 (55.9%) aged 20-24 years. Almost all were male (99%). Being aged 13-17 years (adjusted odds ratio 1.25; 95% CI 1.11, 1.42) and 18-19 years (adjusted odds ratio 1.26; 95% CI 1.10, 1.43) were associated with higher odds of severe injury compared with being aged 20-24 years.

Conclusion: Motorcycle riders who presented to the hospital with injuries after road traffic crashes and were aged 13-17 years and 18-19 years had significantly higher odds of severe injury than those aged 20-24 years.