Risk compensation theory should be subject to systematic reviews of the scientific evidence
- 1Harborview Injury Prevention and Research Center, Department of Pediatrics, University of Washington, Seattle
- 2Department of Preventive Care, Group Health Cooperative of Puget Sound, Seattle
- Correspondence to: Diane C Thompson, Harborview Injury Prevention and Research Center, Box 359960, 325 Ninth Avenue, Seattle, WA 98104, USA dct{at}u.washington.edu
“Risk compensation theory should be subject to systematic reviews of the scientific evidence” (Thompson, Thompson, and Rivara) and “The risk compensation theory and bicycle helmets”(Adams and Hillman) plus authors' responses are being republished electronically in a different order at the authors' request to avoid any potential confusion (Injury Prevention 2002;8:e1; http://www.injuryprevention.com/cgi/content/full/8/2/e1). They were previously published in June 2001 (Injury Prevention 2001;7:86–91).
BACKGROUND
Many readers of Injury Prevention are quite familiar with the debate over bicycle helmet use. The core of this debate is the opinion on one side that helmets are effective and thus should be worn, countered on the other side by the belief that risk compensation negates this protective effect of helmets. A systematic review on helmet effectiveness has been published in the Cochrane Library.1 The objective of the Cochrane review was to determine whether bicycle helmets reduce head, brain, and facial injury for bicyclists of all ages involved in a crash. The principles required of high quality evidence based reviews were followed: a comprehensive literature search, pre-established study selection criteria, and most importantly a critical review of study methods. A well conducted systematic review identifies and considers all the literature (peer reviewed, government reports, and unpublished papers), and rates the study quality. Appropriately, such reviews only include better designed and conducted studies. The evidence is then summarized across all the studies.
The literature search for the Cochrane review yielded five studies meeting the pre-established criteria for inclusion. The strengths and weaknesses of five case-control studies of bicycle helmet effectiveness were carefully evaluated. The scientific evidence which indicates that bicycle helmets protect against head, brain, severe brain and facial (upper and mid-face) injuries has been well established. Additionally, the evidence indicates that helmets provide injury protection in all type of crashes including those involving motor …
