Impact of Laboratory Charge Display Within the Electronic Health Record Across an Entire Academic Medical Center: Results of a Randomized Controlled Trial.

Objectives: To determine the impact of system wide charge display on laboratory utilization. Methods: This was a randomized controlled trial with a baseline period and an intervention period. Tests were randomized to a control arm or an active arm. The maximum allowable Medicare reimbursement rate was displayed for tests in the active arm during the intervention period. Total volume of tests in the active arm was compared with those in the control arm. Residents were surveyed before and after the intervention to assess charge awareness. Results: Charge display had no effect on order behavior. This result held for patient type (inpatient vs outpatient) and for insurance category (commercial, government, self-pay). Residents overestimated the charges of tests both before and after the intervention. Many residents failed to notice the charge display in the computerized order entry system. Conclusions: The impact of charge display depends on context. Charge display is not always effective.