Adolescents are at a greater risk of being involved in traffic accidents than most other age groups, even before they start driving cars. This article aims to determine the factor structure of a self-report questionnaire measuring adolescent risky cycling behaviour, the ACBQ (Adolescent Cycling Behaviour Questionnaire). The questionnaire's structure was based on the widely used Driver Behaviour Questionnaire (DBQ). A sample of secondary school students (N = 1749; age range: 13-18 years) filled out the questionnaire. Factor analysis revealed a three-factor structure underlying the questionnaire, which was confirmed on two equally large portions of the entire sample. These three underlying factors were identified as errors, common violations and exceptional violations. The ACBQ is a useful instrument for measuring adolescents' risky cycling behaviour.

Health risk judgments are not merely based on risk statistics but also on the ease with which hypothetical events are imagined. We explored the effects of scenario information as opposed to frequency information on susceptibility perceptions regarding Chlamydia and HIV. Results showed that participants felt more susceptible to Chlamydia after reading frequency information. Scenario information only seemed to affect feelings of susceptibility in participants with no intimate relationship. No effects on perceived susceptibility for HIV were found. Results are discussed in terms of severity of the disease and defensive reactions.

In The Netherlands, 12-24 years old are over-represented in the total number of traffic fatalities and injuries. In this study, the traffic informer program - designed to promote safe traffic behavior in the pre-driver population - was experimentally evaluated, with a specific focus on bicycle use. Students were subjected to graphic videos of traffic accidents and listened to a first-person narrative provided by a traffic accident victim. The influence of the program on concepts derived from the theory of planned behavior and protection motivation theory (attitudes, norms, self-efficacy, risk-perception, intention and behavior) was assessed. Students from various schools (N=1593;M age=15 years, SD=.84) participated in a quasi-experimental study, either in an experimental or a control group, completing self-report questionnaires one week prior to the program implementation and approximately one month after the program implementation. Mixed regression analyses showed significant positive and negative time × intervention interaction effects on attitude toward traffic violations, relative attitude toward traffic safety, and risk comparison, but not on intention and behavior. More research is needed to find effective behavioral change techniques (other than increasing risk awareness) for promoting safe traffic behavior in adolescents. Research is also needed to address how these can be translated into effective interventions and educational programs.

The marked inversion of the relative risk estimate can be considered a practical example of confounding by contraindication.