Providers were more miserly about ordering tests when they know ahead of time how much they would cost, a study found.
To determine whether providing costs of tests would reduce the number of laboratory tests ordered, researchers conducted a controlled clinical trial among physicians and nonphysicians using computerized order entry at The Johns Hopkins Hospital.
Researchers randomly assigned 61 diagnostic laboratory tests to an "active" arm (fee displayed) or to a control arm (fee not displayed). No fee data were displayed for six months, from November 2008 through May 2009, and then fee data was displayed from November 2009 through May 2010.
Results appeared online April 15 at JAMA Internal Medicine.
When fees were displayed, rates of test ordering fell from 3.72 tests per patient-day in the baseline period to 3.40 tests per patient-day in the intervention period (8.59% decrease; 95% confidence interval [CI], -8.99% to -8.19%). When fees weren't displayed, ordering increased from 1.15 to 1.22 tests per patient-day from the baseline period to the intervention period (5.64% increase; 95% CI, 4.90% to 6.39%) (P less than .001 for difference over time between active and control tests).
First author Leonard S. Feldman, MD, FACP, and co-authors noted that the six-month intervention resulted in a $400,000 net charge reduction.
"If the intervention is broadened, targeting the most frequent tests would probably yield the most success because the expensive tests are ordered too infrequently to affect outcomes significantly," the authors wrote. "It is notable that we offered no direct or indirect incentives for changing ordering behavior, suggesting that physicians can act in a cost-conscious manner even without direct incentives."