Drs. Ross Baker, Peter Norton and colleagues found that 7.5% of patients experienced an adverse event and of that number 37% were judged to have been preventable. The authors point out that although most of the patients who experienced an adverse event recovered without permanent disability (64%), 21% of AEs resulted in death and of this number 9% of the events were judged to have been preventable. The authors state that an extrapolation of these figures based on 2.5 million total hospital admissions in 2000 suggests that between 9250 and 23 750 deaths from AEs could have been prevented.
The study's findings indicate Canada's AE rate of 7.5% is lower than the rates reported in several other large studies in New Zealand and Australia, but potentially higher than rates found in two US studies.
The authors suggest gains in improving patient safety can come from encouraging reporting of AEs, continued monitoring of the incidence of these events, the application of new technologies and improving communication and coordination among caregivers.
Dr. Peter Davis, coauthor of a similar study of New Zealand hospitals, says in a related commentary that some of the blame for adverse events should lie with "the paradigm of modern medicine itself." He suggests that, patients are moved to higher levels of intervention within a hospital-oriented referral system, perhaps to their own detriment. Davis recommends re-examination of this practice, particularly for older patients who suffer the greatest proportion of adverse events.
p. 1678 The Canadian Adverse Events Study: the incidence of adverse events among hospital patients in Canada
-- G.R. Baker et al
p. 1688 Health care as a risk factor
-- P. Davis