A test of a linear discriminant for identifying low-risk abdominal pain.

This study tests a previously published decision rule for identifying nonspecific abdominal pain (NSAP). The rule, developed for ambulatory male patients in two Veterans Administration (VA) facilities and a prepaid group practice, was studied in an additional 110 VA patients and in 77 patients (predominantly female) from a solo private practice. The group of 58 patients (33%) classified as "low-risk" rarely had abnormal laboratory tests or radiographs, except for upper gastrointestinal series; 15 of these patients had potentially serious disease. Peptic ulcer was the specific diagnosis most often misclassified as NSAP. The accuracy of the rule in our population is similar to the accuracy of the judgment of experienced clinicians.

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.