To determine whether parachutes are effective in preventing major trauma related to gravitational challenge.
Systematic review of randomised controlled trials.
Medline, Web of Science, Embase, and the Cochrane Library databases; appropriate internet sites and citation lists.
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.
We were unable to identify any randomised controlled trials of parachute intervention.