Improving Test Ordering Must Also Address Underutilization of Appropriate Tests, Study Finds

Misuse of laboratory testing is common, but new research suggests that underutilization of appropriate tests may actually be more prevalent than overutilization of unnecessary tests. Analysis of 15 years of published data on appropriateness of test orders shows that overutilization of testing is a systematic problem and accounts for nearly one-third of ordered tests, but underutilization is as widespread, and understudied. By improving test ordering, particularly in the initial evaluation, more cost-effective care can be achieved, say the authors of the study published Nov. 15 in PLoS One. “It’s not ordering more tests or fewer tests that we should be aiming for, it’s ordering the right tests, however few or many that is,” says senior author Ramy Arnaout, M.D., D.Phil., in a statement. “Remember, lab tests are inexpensive. Ordering one more test or one less test isn’t going to ‘bend the curve,’ even if we do it across the board. It’s everything that happens next—the downstream visits, the surgeries, the hospital stays—that matters to patients and to the economy and should matter to us.” The researchers examined published studies (from 1997, the year of the last published review of lab tests, to 2012) to identify 42 papers covering 1.6 million tests representing 46 of the 50 most commonly ordered lab tests (including complete blood counts, basic metabolic panels, D-dimer, and HIV tests). The studies all assessed the appropriateness of the tests as measured by subjective versus objective appropriateness criteria and restrictive (clear indication for ordering) versus permissive appropriateness criteria (no contraindication to ordering), terms coined by the authors. “You’d never have a situation where you drop a loved one off at the doctor and when you pick them up at the end of a day, they’re missing a foot because the doctor went down a checklist and couldn’t see any reason not to remove the foot. That doesn’t happen because medicine adheres to ‘restrictive’ policies,” explains Arnaout, associate director of the clinical microbiology laboratories at Beth Israel Deaconess Medical Center in Boston. “Laboratory medicine is the exception to this rule. In ordering blood tests, we too often tend to be permissive, asking ‘why not?’ instead of ‘why?’” The researchers found that the overall mean rate of overutilization was 20.6 percent, compared to 44.8 percent for underutilization. A general emphasis on studies evaluating overutilization compared to underutilization during the study period precluded subgroup analysis of the underutilization rates. However, the researchers discovered several significant trends pertaining to overutilization of testing:

• During initial testing, overutilization was six times higher than during repeat testing (mean of 43.9 percent versus 7.4 percent).

• Low-volume tests were overutilized three times more often than high-volume tests (32.2 percent versus 10.2 percent).

• Using restrictive criteria, overutilization was three times higher than when measured using permissive criteria (44.2 percent versus 12 percent).

• Using subjective criteria to measure overutilization versus objective criteria resulted in rates twice as high (29 percent versus 16.1 percent).

No significant differences were seen in overutilization trends over time or by type of test (chemistry, hematology, microbiology, and molecular). Given the heterogeneity of tests and testing indications, the authors say that in performing pooled analysis they controlled for potential biases in pooling and the patterns remained robust revealing “broad, consistent, clinically valuable patterns” in overutilization that are “likely representative of practice across medicine.” In an environment focused on cost cutting, emphasis on the financial impact of misuse of laboratory testing must be quantified and not just using the face value of the tests, the authors say. “Improving laboratory utilization should lead to more cost-effective care, regardless of whether more appropriate utilization leads to fractionally lower, or even fractionally higher, testing costs,” conclude the authors. Takeaway: Overutilization of testing is a systematic problem, but underutilization is just as widespread. Aiding physician education efforts to improve compliance with national guidelines provides laboratories an opportunity to potentially boost some testing volumes, while playing a meaningful role in improving cost-effectiveness of care.    Side Bar Box: Mounting Evidence Shows Passive EHR Pricing Info Influences Test Ordering There are growing calls to rein in duplicative or unnecessary diagnostic testing, yet efforts are stymied by physicians’ lack of knowledge of the financial impact their clinical management decisions have on the bottom line. New evidence shows, though, that real-time, passive display of laboratory test cost information in an electronic health record (EHR) can lead to a modest reduction in test ordering and is well received by physicians, according to a study published in the November issue of the Journal of General Internal Medicine. Primary care physician ordering of common laboratory tests was evaluated in five allied group practices in Massachusetts, with existing financial risk-bearing payer contracts. From April 2010 to November 2011, 153 primary care physicians participated in the intervention (an EHR display of average Medicare reimbursement rate for 27 laboratory tests at the time of ordering), while 62 physicians not seeing the display were used as controls. Of the 27 laboratory tests included in the intervention, 21 cost less than $40 per test (“lower-cost tests,” such as basic metabolic panels, glucose, iron, lipid, and urine testing) and six tests that cost more than $40 per test (“higher-cost tests,” such as vitamin D, parathyroid hormone, and chlamydia testing). The researchers, from Massachusetts General Hospital in Boston, found that the cost displays resulted in a modest reduction of 0.4 to 5.6 laboratory orders per 1,000 visits per month. However, the intervention led to significantly decreased ordering rates for five tests. Of the five tests ordered less frequently, four were lower-cost test (ALT liver function, creatinine, glucose, and lipid profiles) and one was a higher-cost laboratory test (chlamydia/GC urine screen). Nearly one-third of intervention physicians reported that they considered the information in the laboratory cost displays “always” or “usually,” while a clear majority (81 percent) reported an improved knowledge of the relative costs of laboratory tests with the intervention.