The Boston Collaborative Drug Surveillance Program (BCDSP) and the methods it employs have been described previously in The Journal.1 The program is designed to collect and analyze data on therapeutic and diagnostic drug usage in the medical wards of nine cooperating hospitals in three countries. While the goals are to reveal several aspects of information about drug usage, including the detection of unsuspected adverse reactions, a major purpose is to provide quantitative data on known reactions.
If a prescribing physician is to make an intelligent appraisal of risks vs expected benefits from a drug, he needs at least a reasonable estimate of the likelihood of an undesired effect. Schemes for the spontaneous reporting of adverse reactions have generally proven futile in revealing any approximation of the incidence of a given reaction within the population exposed. The BCDSP, through careful monitoring of a finite patient population, provides a quantitative measure