HealthDay News — Despite growing concerns about health-care costs, repeat testing is common without evidence of a clear benefit, study findings show.
As many as one-third to one-half of a large cohort of Medicare beneficiaries had repeat tests performed within three years, H. Gilbert Welch, MD, MPH, of Dartmouth College in Lebanon, N.H., and colleagues reported in Archives of Internal Medicine.
Furthermore, wide variations in repeat testing rates were noted from place to place, suggesting that clinicians in certain regions are more likely to repeat unnecessary exams than others.
“Although the tests themselves pose little risk, repeat testing is a major risk factor for incidental detection and overdiagnosis,” the researchers wrote.
Unnecessary testing reduces the ability to serve new patients and increases costs for existing patients, but few studies have examined testing habits in ever day practice. So welch and colleagues examined patterns of repeat testing in a longitudinal study involving a random sample of 743,478 Medicare beneficiaries who were alive for three years after their index test conducted from Jan. 1, 2004 through Dec. 31, 2006.
Six commonly performed tests were chosen because they were familiar to clinicians, but there is no consensus on how often repeat testing is necessary: cystoscopy, upper endoscopy, pulmonary function, chest computed tomography, echocardiography, and imaging stress test, either nuclear or stress echocardiography.
The researchers found that repeat testing within three years was common among the following examinations:
- Echocardiography — 55%
- Imaging stress tests — 44%
- Pulmonary function tests — 49%
- Chest computed tomography — 46%
- Cystoscopies — 41%
- Upper endoscopies — 35%
Across metropolitan statistical areas, the proportion of the population tested and proportion of tests repeated varied. For example, the proportion of patients who underwent echocardiography was highest in Miami at 48% with 66% undergoing repeat examination within three years, and lowest in Portland, Ore. at 18%, with 47% of examinations repeated.
Across 50 metropolitan statistical areas, there was a consistent and significant positive association between the proportion of the population tested with the proportion of tests repeated.
In an accompanying editorial, Jerome Kassirer, MD, of Tufts University School of Medicine in Boston, and Arnold Milstein, MD, of Stanford University School of Medicine in Palo Alto, Calif., wrote that the findings were “disappointing” in light of recent efforts to curb wasteful health-care spending.
They acknowledged that although repeat testing is necessary in some instances, if the initial test was flawed for example, repeating tests to avoid litigation or increase profits is not justified.
“Likely, the most powerful cause of unjustified testing is financial incentives” Kassirer and Milstein added, noting that many clinicians privately acknowledge this to be the case.