What makes these numbers especially alarming is that the study says it does not count drug incidents resulting from mistaken prescriptions by doctors or the administration of wrong doses by nurses. The numbers, nevertheless, may be somewhat misleading. Much of the data come from teaching hospitals, which treat sicker patients and administer more risky drugs, and therefore produce more adverse drug reactions than do other hospitals. The study also uses a controversial technique that combines imprecise studies to reach a statistically definitive conclusion. The nation's leading expert on drug incidents in hospitals, Dr. Lucian Leape of Harvard Medical School, says the report leaves unanswered how many of the estimated drug reactions are truly mistake-free.
Some cancer drugs are particularly dangerous and risk damaging the heart or other vital organs.
Mishaps from these drugs are inevitable no matter how careful a hospital's procedures. The report does not say how many of its estimated fatalities and other problems could have been avoided with better monitoring procedures. Besides mistake-free accidents, perhaps an additional 200,000 hospital patients suffer preventable injuries. Dr. Leape and his colleagues help hospitals devise procedures for preventing wrong prescriptions and incorrect doses. But many error-prevention procedures are not commonly used.