BMJ. 2003 Dec 20;327(7429):1459-61. Republished in: Int J Prosthodont. 2006 Mar-Apr;19(2):126-8. Smith GC, Pell JP. Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials. Department of Obstetrics and Gynaecology, Cambridge University, Cambridge CB2 2QQ. [email protected] OBJECTIVES: To determine whether parachutes are effective in preventing major trauma related to gravitational challenge. DESIGN: Systematic review of randomised controlled trials. DATA SOURCES: Medline, Web of Science, Embase, and the Cochrane Library databases; appropriate internet sites and citation lists. STUDY SELECTION: Studies showing the effects of using a parachute during free fall. MAIN OUTCOME MEASURE: Death or major trauma, defined as an injury severity score > 15. RESULTS: We were unable to identify any randomised controlled trials of parachute intervention. CONCLUSIONS: As with many interventions intended to prevent ill health, the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomised controlled trials. Advocates of evidence based medicine have criticised the adoption of interventions evaluated by using only observational data. We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute.