Medicare Beneficiaries and Repeat Testing

The capacity for physicians to serve new patients and the ability to contain costs of healthcare are determined, in part, by the tendency to repeat examinations. Physicians who see their patients every 12 months can care for twice as many patients as those who routinely see patients every 6 months, which has reduced provider costs by half. Varying thresholds and intervals for repeating diagnostic tests have similar implications: low thresholds and short intervals to repeat testing raise costs and require increased capacity to provide access for new patients.

Little is known about appropriate thresholds and intervals for repeat testing in specific clinical settings. For example, the American Urological Association notes that the most common recommendation for surveillance for bladder cancer is cystoscopy every 3 months in the first 2 years after initial treatment, followed by every 6 months for the next 2 to 3 years, and then annually thereafter. This recommendation has been in place since 1936 and has an “uncertain origin,” according to researchers.

The researchers recently conducted an investigation into patterns of repeat testing intervals used in actual practice in the United States. They reported results of their investigation online in Archives of Internal Medicine [doi:10.1001/2013.jamaintermed.727].

The examinations included in the investigation were cystoscopy, upper endoscopy, pulmonary function test, chest computed tomography, echocardiography, and imaging stress test (nuclear stress and stress echocardiography). These tests were selected for inclusion because they are common and familiar to physicians and there is uncertainty as to whether to repeat them and how often. As a frame of reference, the researchers also included 2 examinations that are routinely expected to be repeated at regular intervals: (1) screening mammography (every 1 or 2 years) and (2) eye examinations (every year).

The analysis was done on longitudinal data from a 5% random sample of Medicare beneficiaries between January 1, 2004, and December 31, 2009. The sample was restricted to 743,478 fee-for-service beneficiaries who were alive for a 3-year period following their index test between January 1, 2004, and December 31, 2006. The researchers used the 50 largest metropolitan statistical areas as the unit of analysis to examine the relationship between the proportion of the population tested and the proportion of tests repeated among those tested.

As expected, patients receiving eye examinations and screening mammography were most likely to have repeat testing (79% and 72% of those tests were repeated within 3 years, respectively). For eye examinations, the median interval was 6.1 months; for screening mammography, the median interval was 13.1 months.

Among the 6 examinations not routinely expected to be repeated selected for this analysis, the most frequently repeated test was echocardiography. The test was repeated in 55% of patients within 3 years; the median interval was 12.1 months. Echocardiography was most commonly repeated annually and imaging stress test was most commonly repeated at intervals >1 year.

The 2 pulmonary examinations were usually repeated at shorter intervals: (1) the pulmonary function test was most commonly repeated in <3 months and (2) the chest computed tomography was most commonly repeated in <6 months.

The analyses found that there was a variation in the proportion of the population tested and the proportion of tests repeated across metropolitan statistical areas. The proportion who underwent echocardiography was highest in Miami, Florida (48%, among whom 66% of tests were repeated in 3 years), and lowest in Portland, Oregon (18%, among whom 47% of tests were repeated in 3 years).

In summary, the researchers stated, “Repeat testing is common among Medicare beneficiaries. Patients residing in metropolitan statistical areas with high rates of population testing are more likely to be tested and are more likely to have their test repeated.”