The Seattle evaluation of computerized drug profiles: effects on prescribing practices and resource use.

Since 1979, all outpatient pharmacy transactions at the US Public Health Service Hospital in Seattle have been captured in a computer system which generates a profile of each patient's active and previously used drugs. We conducted a controlled trial in which patients were allocated to profile or no-profile groups while the computer continued to collect data on everyone. In all, 41,572 clinic visits made by 6,186 patients were studied. The incidence of preventable drug-drug interactions and redundancies was very low and was unaffected by profiles. For unclear reasons, prescription of two interacting drugs on the same visit was significantly more common for patients with profiles. The duration of drug-drug interaction episodes was significantly shorter for profile group patients, perhaps due to earlier detection of the error on subsequent visits. Profiles had no effect on prescribing volume or coordination of drug refill and visit schedules, but profile group patients made about 5 per cent fewer clinic visits than those in the no-profile group. In this setting, it appears that the prescribing of interacting or redundant drugs is more often due to inadequate provider knowledge than to inaccessible patient-specific drug data. Prevention of such errors would thus require a more active educational or monitoring program.

The Seattle evaluation of computerized drug profiles: effect on provider activities.

We studied whether furnishing care providers with computer-generated summaries of patients' current and past medications would reduce the time they spent on various drug-related tasks during patient visits. An observer used time-sampling methods to measure the amount of provider time spent on each of 10 activities during 166 clinic visits, some with profiles and some without them. Additional data were taken from the medical record on factors that might affect the time spent on various tasks. The results suggest that record reading time was reduced for first encounters between patients and providers in the medical clinics, where prescribing volume was highest; in other situations, no effect of profiles on record reading time was evident. Providers continued to document drug data in their progress notes, whether or not a profile was available, saving no time. Prescription writing required about one third less time when a profile was used than when a traditional prescription blank was used. Both uses of profiles for prescribing and the time saved per prescription also increased sharply with the number of drugs prescribed per visit.