Multiple Risk Behavior and Injuries: An International Analysis of Young People

Background: Multiple risk behavior plays an important
role in the social etiology of youth injury, yet the
consistency of this observation has not been examined
multinationally.
Objective: To examine reports from young people in
12 countries, by country, age group, sex, and injury type,
to quantify the strength and consistency of this association.
Setting: World Health Organization collaborative crossnational
survey of health behavior in school-aged children.
Participants: A multinational representative sample of
49461 students aged 11, 13, and 15 years.
Main Exposure Measures: Additive score consisting
of counts of self-reported health risk behaviors: smoking,
drinking, nonuse of seat belts, bullying, excess time
with friends, alienation at school and from parents, truancy,
and an unusually poor diet.
Main Outcome Measure: Self-report of a medically
treated injury.
Results: Strong gradients in risk for injury were
observed according to the numbers of risk behaviors
reported. Overall, youth reporting the largest number
(
5 health risk behaviors) experienced injury rates that
were 2.46 times higher (95% confidence interval, 2.27-
2.67) than those reporting no risk behaviors (adjusted
odds ratios for 0 to
5 reported behaviors: 1.00, 1.22,
1.48, 1.73, 1.98, and 2.46, respectively; P.001 for
trend). Similar gradients in risk for injury were
observed among youth in all 12 countries and within all
demographic subgroups. Risk gradients were especially
pronounced for nonsports, fighting-related, and severe
injuries.
Conclusions: Gradients in risk for youth injury increased
in association with numbers of risk behaviors reported
in every country examined. This cross-cultural
finding indicates that the issue of multiple risk behavior,
as assessed via an additive score, merits attention as
an etiological construct. This concept may be useful in
future injury control research and prevention efforts conducted
among populations of young people.