We found that physicians and patients had markedly different perspectives on barriers to CRC screening. Although physicians reported offering screening to most of their average-risk patients, they acknowledged limited adherence. Physicians most often cited patient factors as being frequent barriers, including fear of pain, embarrassment and anxiety about testing, lack of insurance, and lack of knowledge about cancer and screening. Meanwhile, population-based data from adults aged 50 years or older showed that they rarely considered discomfort or embarrassment to be a primary barrier. Respondents were far more likely to report that lack of a physician recommendation or lack of symptoms prevented them from getting tested.
Other investigators have also noted a discrepancy between physician and patient perspectives on barriers, though not at a statewide level. Klabunde and colleagues compared results from nearly concurrent national surveys of providers (1999-2000 Survey of Colorectal Cancer Screening Practices) and adults in the general population (2000 National Health Interview Survey [NHIS]) (15
). Investigators asked a nationally representative sample of primary care providers to rate the importance of patient and health care system barriers to screening with either FOBT or lower endoscopy. More than 90% of the physician respondents identified at least 1 major barrier, more often patient-related (80%) than system-related (68%). The most frequently cited patient barriers were embarrassment/anxiety about testing (56%), lack of awareness of screening/not perceiving the seriousness of CRC (48%), and fear of finding cancer (28%). The most frequently cited system barrier was financial (46%). In contrast, only 1% of NHIS respondents reported concerns about pain or embarrassment as major barriers for lower endoscopy. The most frequently cited barriers by patients were not seeing a need for testing/lack of awareness (51%), which was concordant with the physicians' responses; however, 21% also reported that their doctor did not order or recommend the test.
Physicians' failure to discuss screening is a common theme in patient surveys. Even though lack of time to discuss screening was not seen as a frequent barrier by our respondents, the literature suggests otherwise. Yarnall and colleagues estimated that it would take 7.4 hours a day for a provider in an adult primary care practice to address the preventive services deemed effective by USPSTF (21
). Competing health demands can make it difficult to address screening during routine office visits, and a meta-analysis found that conducting a prevention visit was significantly associated with being able to deliver more screening (22
Additionally, only one-third of our respondents reported that their practice had written policies for CRC screening, and availability of tracking systems and electronic medical records was limited. This may be an unrecognized provider barrier to discussing screening. Inadequate use of office systems has been identified as a major barrier for achieving screening (23
). Developing office policies is seen as a necessary first step to ensuring system changes (25
), and employing a tracking system can facilitate effective screening by identifying patients who are due for screening (or surveillance) — and ensuring that results of screening and diagnostic tests are documented (24
Physician-patient communication about CRC screening may be less than ideal. Our results suggest that physicians may not be fully aware of patients' attitudes and values toward screening. Ling and colleagues studied attitudes toward CRC screening among physicians and patients at a single academic practice (26
). Physicians markedly overestimated test discomfort as a barrier compared with patients and underestimated the importance of test accuracy for patients. Physicians may also not recognize the importance of helping patients make informed decisions for screening. CRC screening is a complex issue because multiple testing options are available, and various criteria are used to assess risks (27
). These concepts can be difficult to convey, and the literature suggests that discussions often do not take place (29
) or are inadequate (30
). One study analyzed audiotaped clinic visits and found that although 40% of discussions provided patients with background information about screening, most did not address alternatives (74%) or pros and cons (83%), or elicit patient preferences (83%). Conversely, providing patients with a CRC screening decision aid that informed them about cancer risks and available effective tests was associated with a significant increase in completing screening tests (32
The physician survey responses also revealed some implicit barriers to effective screening. Physicians believed that colonoscopy was more effective than FOBT and flexible sigmoidoscopy. This finding mirrors national survey results (33
) and may be attributed to guidelines that rate colonoscopy as the optimal test (34
). However, the objective evidence for screening effectiveness for FOBT is based on randomized controlled trials (2
), whereas only case-control and observational data support the effectiveness of colonoscopy (35
). Consequently, USPSTF gives an overall "A" rating to CRC screening, without recommending any specific tests (27
). In New Mexico, capacity for colonoscopy is limited (38
), suggesting that using alternative tests may be necessary to achieve higher screening rates.
Another issue was the potential for overscreening elderly patients. Among respondents to the questions about stopping screening, 63% did not indicate any upper age for stopping FOBT, while 55% of those who set an upper age for colonoscopy would continue recommending screening past age 80. USPSTF recommends that screening not be offered for patients aged 85 years or older and offered only after a risk-benefit discussion with patients aged 76 to 84 years because patients with limited life expectancy have little expected benefit from screening (27
). Other provider surveys have also indicated insufficient consideration of patient age when making screening recommendations (39
). Although the FOBT is inexpensive and safe, false-positive results are common and abnormal studies require diagnostic colonoscopy. Screening patients who are unlikely to receive any benefit is an inefficient use of resources.
Our study had some potential limitations. The overall response rate to the physician survey was low, creating a potential selection bias if respondents were not representative of the population of New Mexico primary care physicians. However, a recent New Mexico Health Policy Commission (NMHPC) report suggests that the demographics of our sample were consistent with statewide data on primary care physicians (41
). In 2008, the NMHPC reported that 43% of primary care physicians were aged 55 or older (vs 39% in our sample), 56.9% were men (vs 68%), and 48% were in the county containing Albuquerque (vs 47%). We also know that our denominator of potentially eligible physicians was not accurate and that we likely underestimated our response rate. We relied on the Board of Medical Examiners physician listings, which do not consistently characterize specialty or training status, so we may have misclassified specialists and trainees as being primary care physicians. Contact information is updated only every 3 years, so we could not be certain that we had correct addresses. However, our results in terms of practice patterns, system support, and barriers are consistent with those of other surveys reporting higher response rates (15
). We were also unable to verify provider responses regarding screening practices and adherence.
The BRFSS data are subject to selection and recall bias, although reports of physicians failing to recommend screening are supported by national surveys (15
) as well as directly observed patient encounters (31
). Social desirability bias may have caused respondents to minimize fear and embarrassment as screening barriers. Finally, our data are ecologic; physician and BRFSS respondents are not directly linked, which could result in differing perceptions of barriers, particularly related to access.
Our results suggest that CRC screening in New Mexico could be facilitated by information systems that readily identify patients who are due for screening and track test results. Physicians may also increase screening by educating patients about cancer and the rationale and options for screening. Physicians in a state with limited resources for cancer screening should also avoid potentially inefficient (not having an upper age limit for FOBT screening) and impractical (emphasizing screening colonoscopy) screening strategies.