Rising health care expenditures in the United States encourage physicians to provide quality patient care while eliminating wasteful spending. Reference laboratory tests represent a small percentage of a hospital’s total test volume, but a disproportionate percentage of laboratory costs. Our goal was to examine the effect of displaying inpatient reference laboratory test costs and turn‐around times on physician ordering behavior.


We designed a prospective cohort study at a tertiary care teaching hospital involving inpatient attending physicians and residents where physician ordering behavior was prospectively observed between September 2010 through December 2012. An intervention was implemented to display cost and turn‐around time for reference tests within our computerized physician order entry system. We examined changes in the mean number of monthly physician orders, the mean cost per order, and the average turn‐around time per order.


Reference test cost and turn‐around time were poorly correlated (r=0.33). After implementation of cost and turn‐around time feedback, the mean number of monthly physician reference test orders decreased by 23% with a mean cost decrease per test of $12.30. Sub‐group analysis showed a mean decrease in average turn‐around time per test by 4% in the low cost group and 15% in the high cost group. The intervention projected a mean annual savings of $330,439. The overall reduction in ordering volume was seen despite an increase in monthly inpatient days over the same time period.


Display of reference laboratory cost and turn‐around time data during real time ordering may result in significant decreases in ordering of reference laboratory tests with subsequent cost savings. Turn‐around time may be an independent factor in decreasing physician ordering.