Outcome Criteria

All the studies reviewed include at least one of the outcomes listed below. An intermediate outcome would be crash events, or violations. An observed behavior would be seat belt use, helmet use, etc. We did not review studies which used self-reported outcomes or changes in beliefs, attitudes or knowledge. For example the success of a campaign to increase bicycle helmet use could be based on observations but not self reported use. 

Outcomes Evaluated in Reviewed Studies 

  • Risk of death 
  • Risk of hospitalization
  • Risk of injury requiring ED Care
  • Risk of injury requiring physician care in other setting
  • Change in injury severity
  • Change in intermediate outcomes (please specify, e.g. reduction in crash or fall events)
  • Change in measured (observed) behavior (please specify, e.g. wearing bicycle helmets)
  • Change in costs 
Outcomes Excluded from Reviews 
  • Changes in knowledge
  • Changes in attitudes
  • Changes in beliefs
  • Changes in self-reported behavior 
These outcomes were excluded because there is substantial evidence that changes in knowledge, attitudes and beliefs do not correlate with changes in actual behavior and a reduction in injuries ( see references below). 
  •  Assum T. Attitudes and accident risk. Accid Anal Prev 1997; 29:153-9.
  • Joshi MS, Beckett K, Macfarlane A. Cycle helmets in teenagersódo health beliefs influence behavior. Arch Dis Child 1994; 71:536-9.
  • Mawson AR, Buindo JJ. Contrasting beliefs and actions of drivers regarding seat belts: A study in New Orleans. J Trauma 1985; 25:433-437.
  • McLoughlin E, Vince CJ, Lee AM et al. Project Burn Prevention: outcome and implications. Am J Pub Health 1982; 72:241-247.
  • Van Schagen IN, Brookhuis KA. Training young cyclists to cope with dynamic traffic situations. Accid Anal Prev 1994; 26:223-30.
Reported behavior change is not as reliable as directly observed behavior. For example, individuals over-report seat belt use when compared to actual observations of seat belt use (Stulginskas JV, Verreault , Pless IB. A comparison of observed and reported seat belt use by children and adults. Accid Anal Prev 1985; 17:381-6.). Likewise, recent data indicate that individuals over-report bicycle helmet use ( ref ). We therefore have chosen not to include reports in which self-reported behavior change is the only outcome measure. 

Finally, we have also excluded studies in which the outcome has not be clearly shown to be related to risk of injury. For example, in studies of child abuse, many reports used parenting skills or the home environment as outcome measures. These were excluded since the link between changes in these outcomes and risk of injury form abuse has not been established. In contrast, studies in which the outcome was seat belt use or bike helmet use were included, because there are data showing a direct link between changes in these outcomes and changes in rates of injury.