In this study, we used data from a nationally representative survey of primary care physicians to evaluate the extent to which physicians’ CRC screening recommendations for average risk patients were guideline-consistent. Although few physicians made recommendations that were guideline consistent for all CRC modalities they recommended (19%), a larger portion made at least some recommendations that were guideline consistent (40%). A comparable proportion (41%) made CRC screening recommendations for which none were guideline consistent. A major contribution of this study is that we evaluated whether U.S. physicians’ recommendations are guideline consistent across the menu of CRC screening modalities.
The proportion of physicians making guideline-consistent screening recommendations was higher in 2007 than reported in a prior national survey of primary care physicians conducted in 2000.35
Across individual CRC screening modalities, more physicians recommended initiating screening at age 50 and recommended intervals for most modalities were more likely to be guideline consistent in 2007 than in 2000.28
CRC screening practice patterns have changed dramatically over this period with many more physicians recommending colonoscopy in 2007 than in 2000 (95% vs. 37%) and many fewer recommending sigmoidoscopy (26% vs. 76%).23,28
In 2007, the most common combination recommended included colonoscopy and FOBT (76% vs. 35% in 2007 and 2000, respectively); whereas in 2000 the most common combination included FOBT and FS (23% vs. 73% in 2007 and 2000, respectively).28
Differences across this time period likely reflect secular changes, such as implementation of Medicare reimbursement for screening colonoscopy, HEDIS measures for CRC screening, greater consistency across guidelines, as well as changes in physician and practice characteristics.
Others have reported that physician recommendations for specific screening modalities are not consistent with guidelines.19,22,23,28
In this study, most physicians whose CRC screening recommendations were not guideline-consistent recommended initiating screening in their younger patients or at more frequent intervals than prescribed. Importantly, colonoscopy was the modality for which the highest proportion of physicians (approximately 40%) recommended screening more frequently than guidelines specify. It is also the most expensive CRC screening modality and the most commonly recommended. Overuse of screening is expensive for the health care system, and may result in unnecessary follow-up testing for patients36
and increased risk of complications.37
Some physicians recommended initiating screening in patients older than age 50 or at longer intervals than specified in guidelines. Underuse of screening results in fewer earlier stage or pre-invasive cancers being detected. Estimates of the effectiveness and cost-effectiveness of CRC screening are typically based on a specified starting age and screening intervals for each modality; our findings suggest that if CRC screening were evaluated as applied in practice, estimates of the effectiveness and cost-effectiveness might be substantially different. For example, increasing the frequency of screening colonoscopy from every 10 years to every 5 years increases costs and complications with little improvement in survival.38
As has been reported elsewhere, younger, board certified physicians in larger practices were more likely to make guideline-consistent screening recommendations.19,25,28,39
Other components of our theoretical framework were significantly associated with guideline-consistent recommendations. In the domain of practice environment and practice patterns, several variables were associated with screening performance, including geographic region. Area-level primary care physician supply has been previously reported to be associated with CRC screening utilization40
and stage of CRC diagnosis.41
Geographic variation in practice patterns and guideline-consistent CRC screening recommendations may also reflect unmeasured population characteristics, differences in state level health insurance coverage requirements, health care programs or other area-level factors. Understanding the role of these geographic characteristics on health outcomes is an important area for additional research.
Physicians in practices with a full EMR and those in practices transitioning to EMR were more likely to make guideline-consistent recommendations than were physicians in practices with paper charts. Differences between physicians in practices in transition to EMR and those with paper charts likely reflect their early adoption of measures to improve primary care practice rather than a direct effect of a partial EMR. Others have suggested that computerized office reminder systems can improve CRC screening, although the evidence about the impact of EMRs on the quality of care is mixed.42
A strength of our study is that the level of adoption of EMRs was reported by physicians, who are the main users of medical record systems. Future research might also evaluate how the EMRs are being used, namely, for medical record storage, patient-physician and physician-physician communication, or decision support,43
when evaluating quality of care outcomes.
Several of our findings suggest that physicians with more patient-centered practices are more likely to make guideline-consistent recommendations. Physicians who indicated that patient preferences were influential and who reported seeing fewer patients in a typical week were more likely to make guideline-consistent CRC screening recommendations. Others have described the many demands on primary care physicians’ time;44
seeing fewer patients may allow physicians to spend more time with each patient. Physicians who recommended three or four modalities, and might be more likely to offer more options to patients, were also more likely to make guideline-consistent recommendations than were physicians who recommended only one or two modalities. Taken together, these findings suggest that presentation and recommendation of multiple screening options and attention to patient preferences, which are hallmarks of shared decision-making, are also associated with greater quality of care.
In the domain of physician social support and influence, physicians who reported that clinical information in the published literature was influential in their CRC screening practice were more likely to make guideline-consistent recommendations, although surprisingly, we did not observe an association between the perception of guidelines being influential and guideline-consistent screening recommendations. This suggests that efforts to improve delivery of CRC screening should focus on enhancing awareness and understanding of both clinical evidence and guidelines.
Despite the strengths of using a theoretical framework with data from a national sample of primary care physicians with a high response rate and conducting detailed statistical analyses to evaluate our multivariate model development, our study has some limitations. To encourage a high response rate, the survey was relatively brief and did not include questions about factors that may influence screening recommendations, such as disagreement with or misunderstanding of guidelines, or concerns about malpractice. Earlier studies have shown that physician self-report overstates practices they believe to be recommended (e.g., patient receipt of cancer screening45
), although more recent studies suggest that physician self-report of practice is reliable.46
Any idealized reports of practice would imply that guideline-consistent screening recommendations are lower than reported here.
In summary, few primary care physicians made recommendations for CRC screening that were consistent with guidelines for the menu of screening modalities. Physicians’ CRC screening recommendations reflect both overuse and underuse. Implementation of effective interventions that address overuse and underuse of screening and focus on potentially modifiable physician and practice factors will be important for improving screening practice.