title: 1991 air medical helicopter accident rates.
authors: N
authors: N
authors: Preston
mesh_terms: D000060:Accidents, Aviation / Q000706:statistics & numerical data* / Q000639:trends; D000401:Aircraft / Q000706:statistics & numerical data*; D003625:Data Collection; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005069:Evaluation Studies as Topic; D012449:Safety; D014481:United States / Q000453:epidemiology