Randomised or non-randomised studies that evaluated drug interaction software either as a stand-alone product or as part of a larger clinical decision support system that measured outcomes specific to the software were eligible for inclusion. The setting could be in either hospital or community. Outcomes of interest were morbidity or mortality and surrogate outcomes (such as number of potential adverse drug interaction events prevented, adverse drug interaction event rate and the number of inappropriate medications prescribed). Studies were excluded if they did not provide data that provided analysis of drug interaction checking versus control or were published before 1990.
Most of the included studies were conducted in hospital settings; one was conducted in a primary care setting. There was a total of 80,471 patient days/visits. The software was often a component of larger decision support systems rather than an exclusive drug interaction detection software. Control was either no drug interaction software or a handwritten prescription. Studies were undertaken in Canada, Israel and USA.
Two reviewers independently extracted data for the review. Disagreements were resolved by consensus or consultation with a third reviewer.