The effect of algorithms on the cost and quality of patient care.

In a Veterans Administration ambulatory care facility staffed by experienced nurse practitioners, we observed the length of visits, time utilization for various activities, and the use of diagnostic tests before and after introducing algorithms for 12 common chief complaints. Charges for diagnostic tests decreased as much as 40 per cent, primarily because of reduced utilization of radiographs such as spine films. Nurse practitioner productivity was unaffected once the nurse practitioners became familiar with the algorithms. Outcome of illness did not change measurably, but the process of care improved as reflected by more complete data collection documented in the medical record.