Fecal Occult Blood Testing Beliefs and Practices of U.S. Primary Care Physicians: Serious Deviations from Evidence-Based Recommendations Marion R. Nadel, PhD1, Zahava Berkowitz, MSPH1, Carrie N. Klabunde, PhD2, Robert A. Smith, PhD3, Steven S. Coughlin, PhD1,4, and Mary C. White, ScD1 1Division of Cancer Prevention and Control, Centers for Disease Control and Prevention, Atlanta, GA, USA; 2Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD, USA; 3Cancer Control Science Department, American Cancer Society, Atlanta, GA, USA; 4Department of Veterans Affairs, Environmental Epidemiology Service, Washington, DC, USA. BACKGROUND: Fecal occult blood testing (FOBT) is an KEY WORDS: colorectal cancer; cancer screening; primary care; quality important option for colorectal cancer screening that of care; fecal occult blood test. should be available in order to achieve high population J Gen Intern Med screening coverage. However, results from a national DOI: 10.1007/s11606-010-1328-7 survey of clinical practice in 1999–2000 indicated that © The Author(s) 2010. This article is published with open access at Springerlink.com many primary care physicians used inadequate meth- ods to implement FOBT screening and follow-up. OBJECTIVE: To determine whether methods to screen for fecal occult blood have improved, including the use of newer more sensitive stool tests. DESIGN: Cross-sectional national survey of primary INTRODUCTION care physicians. PARTICIPANTS: Participants consisted of 1,134 prima- For more than a decade, major national organizations have ry care physicians who reported ordering or performing strongly recommended routine screening for colorectal can- – cer, the second leading cause of cancer-related death in the FOBT in the 2006 2007 National Survey of Primary 1–10 Care Physicians’ Recommendations and Practices for U.S. Although screening rates have increased, they re- main considerably lower than the rates for other recom- Cancer Screening. 11 MAIN MEASURES: Self-reported data on details of mended cancer screening tests. FOBT implementation and follow-up of positive results. Until recently the most widely used of the recommended RESULTS: Most physicians report using standard screening options was fecal occult blood testing (FOBT), shown to be effective in reducing colorectal cancer incidence and mortality guaiac tests; higher sensitivity guaiac tests and immu- 12–15 nochemical tests were reported by only 22.0% and in randomized controlled trials. However, its effectiveness in 8.9%, respectively. In-office testing, that is, testing of a general clinical practice depends on the degree to which health single specimen collected during a digital rectal exam- professionals follow recommended testing guidelines. A national – ination in the office, is still widely used although survey of primary care physicians conducted in 1999 2000 revealed serious problems in the way many physicians in the inappropriate for screening: 24.9% of physicians report 16 using only in-office tests and another 52.9% report U.S. implemented FOBT in practice. Rather than relying on the using both in-office and home tests. Recommendations multiple-specimen home test that was evaluated in the trials, improved for follow-up after a positive test: fewer 74% of physicians reported performing in-office tests, that is, physicians recommend repeating the FOBT (17.8%) or testing of a single stool specimen collected in the office during digital rectal examination. The in-office test has been shown to be using tests other than colonoscopy for the diagnostic 17 work-up (6.6%). Only 44.3% of physicians who use a very poor test that misses 95% of advanced neoplasia. The home tests have reminder systems to ensure test survey also showed that follow-up of positive FOBTs was often completion and return. inconsistent with recommended standards of practice. Nearly CONCLUSIONS: Many physicians continue to use 30% of physicians recommended repeating FOBT after a positive inappropriate methods to screen for fecal occult blood. result rather than referring the patient for colonoscopy. Sigmoid- Intensified efforts to inform physicians of recommended oscopy, rather than colonoscopy, was commonly recommended technique and promote the use of tracking systems are to work up abnormal findings. Analysis of data from a contem- needed. poraneous survey of adults, the 2000 National Health Interview Survey (NHIS), showed similar results. These observations led one commentator to speculate that, after many years of FOBT testing in the population, colorectal cancer mortality rates might be considerably lower today if more physicians had followed 18 Received September 18, 2009 recommended testing and follow-up methods. Revised February 8, 2010 Since 2000, screening patterns have changed considerably, Accepted February 15, 2010 with colonoscopy becoming the most commonly used colorectal Nadel et al.: FOBT Practices among U.S. Physicians JGIM cancer screening test.11,19,20 However, FOBT is still recom- were asked if they stop the workup if the second FOBT is mended by most primary care physicians.20 It is preferred by a negative. The questionnaire underwent cognitive interviewing significant fraction of adults 21 and is the only test available to and survey materials were pre-tested among a small, randomly- those with insufficient insurance coverage or who live in areas selected sample of primary care physicians. The survey with limited high quality endoscopic services. Using data from questionnaire is available at: http://healthservices.cancer. the National Survey of Primary Care Physicians' Recommenda- gov/surveys/screening_rp/. tions and Practices for Cancer Screening, conducted in late 2006 We assessed follow-up of positive FOBT results in two steps, and early 2007, we reported in a recent paper the tests that as before.16 Among the 1,134 physicians who ordered or physicians recommend for colorectal cancer screening and the performed FOBT at least once per month, we first looked at office systems they use to support screening. We found that 95% whether they recommended repeating the FOBT. We then of primary care physicians routinely recommend colonoscopy examined which tests were recommended for the diagnostic and 80% routinely recommend FOBT for colorectal cancer work-up. At this second step, we did not include respondents screening.20 Indeed, FOBT needs to remain part of every who only reported repeated FOBT (n=104), those who only practice's menu of screening options if high population coverage indicated that they referred patients to another physician for is to be achieved. Growing evidence that the newer FOBTs are follow-up of positive FOBT results (n=28) and those whose superior to the standard guaiac test used in the original response we could not classify (n=3). screening trials suggests that FOBT may be a more effective For the bivariate analyses of data, we performed a log- screening option now than when screening guidelines were first likelihood chi-square test for the association between each of issued.22,23 the various physician or physicians' practice characteristics and Have physicians’ methods for implementing FOBT improved? the outcome variables, i.e., percentage of physicians who use in- Since 2000, more recent versions of national screening guide- office tests (Table 2) and percentage of physicians who repeat lines have explicitly recommended against in-office FOBT and FOBT after abnormal results (Table 3). For the multivariate against repeating FOBT in response to an initial positive analyses, we performed logistic regression using the Wald chi- – finding.5 7,9 Billing codes were changed to emphasize that only square test to test the association between each physician or home tests are appropriate for screening.24 practice characteristic and each of the outcomes described We report here an in-depth analysis of FOBT practices using above while controlling for all other variables in the respective data from the 2006–2007 primary care physician survey to table. We computed predictive margins (adjusted percentages), a assess whether there has been improvement in the methods type of direct standardization that averages the predicted values physicians use to implement FOBT and their beliefs about and from the logistic regression models over the covariate distribu- use of the newer fecal occult blood tests. tion in the population, allowing comparisons across categories of the variables included in the models.25 To permit generaliza- tion of the results of all analyses to the U.S. population of METHODS practicing primary care physicians, we used sampling weights that account for the probability of selection and non-response. The National Cancer Institute (NCI) collaborated with the Centers We used the SAS statistical package, version 9.1.3 (SAS Institute, for Disease Control and Prevention (CDC) and the Agency for Inc., Cary, North Carolina)26, and SUDAAN, version 9 (Research Healthcare Research and Quality (AHRQ) to survey a nationally Triangle Institute, Research Triangle Park, North Carolina)27 to representative sample of primary care physicians between compute estimates, confidence intervals and P values. September 2006 and May 2007. The American Medical Associa- This study was determined to be exempt from review by the tion’s Physician Masterfile was used to form the sample, which institutional review boards at the NCI and CDC. included family practitioners, general practitioners, general internists and obstetrician-gynecologists.