The American Cancer Society (ACS), the U.S. Preventive Services Task Force (USPSTF), and the American Gastroenterological Association (AGA) recommend CRC screening for average-risk individuals starting at age 50 by means of annual fecal occult blood testing (FOBT), flexible sigmoidoscopy once every 5 years, annual FOBT and flexible sigmoidoscopy once every 5 years, colonoscopy once every 10 years, or double contrast barium enema once every 5 years.³ These organizations report insufficient evidence to recommend 1 screening test over another. Based on indirect evidence, the American College of Gastroenterology (ACG) and the American Society for Gastrointestinal Endoscopy (ASGE) endorse colonoscopy as the preferred screening strategy but advocate an alternative when resources for screening colonoscopy are unavailable.^4,5

The AGA asserts that patients “should be offered options for screening, with information about the advantages and disadvantages associated with each approach, and should be given an opportunity to apply their own preferences in selecting how they should be screened.”⁶ Similar statements included in the recommendations of the ACS, USPSTF, ACG, and ASGE are supported by literature suggesting that involving patients in decisions regarding their care may increase their compliance with screening.^7,8 Despite this endorsement of patient choice, however, it is noteworthy that rates of screening colonoscopy have increased dramatically in recent years, whereas those of flexible sigmoidoscopy and barium enema have declined precipitously ^9–11, and rates of screening with FOBT have remained low and stable.¹² In 2004, the Centers for Disease Control and Prevention (CDC) reported that 51% of adults 50 and older underwent an endoscopic screening procedure compared with only 19% who completed FOBT.¹³

The growing dominance of colonoscopic screening raises potential concerns, especially because it is doubtful that many patients are able to carefully consider alternatives during time-limited office visits with primary care providers (PCPs).^14,15 It is possible that by utilizing informed or shared decision making in a more effective manner, we may facilitate improved screening test completion. This is all the more relevant because the CDC estimated in 2004 that 45% of eligible adults age 50 years or older had not been screened, which likely accounts for the high mortality rate still observed for a largely preventable cancer.^2,16 Thus, it is important to determine whether patients prefer an alternative to colonoscopy when given a choice.

When asked to indicate the most important reason for their preference, and 253 respondents did so (Table 2). Overwhelmingly, the most commonly cited reasons were test accuracy (colonoscopy) and test ease and convenience (FOBT), accounting for almost three fourths of all responses. Without difference by test preference, approximately one third of the respondents indicated that they would adhere to their choice even if a physician recommended an alternative. In addition, whereas 44% of all respondents felt “very strongly” about their preference, those choosing FOBT were less likely than those choosing colonoscopy to feel “very strongly” about their choice (Table 3).

These findings are important for at least 2 reasons. First, if patients feel reticent about colonoscopy, it is possible they may forgo screening altogether if they are not offered an alternative, thus limiting the ability to increase rates of any type of CRC screening within the general population. Second, when patients are offered an informed choice—something advocated for ethical reasons by many professional societies^3–6—a large number of patients are likely to prefer an alternative to colonoscopy. However, there is reason to be concerned that clinicians do not adequately present (or patients have little time to carefully consider) alternatives to colonoscopy during time-limited primary care visits. Although we did not identify any studies that confirm or refute this possibility, the common absence of informed decision making for prostate cancer screening—another complicated preventive service—has been well documented.²⁴

Unsurprisingly, a personal history of flexible sigmoidoscopy and a family history of CRC were both associated with a preference for colonoscopy over FOBT. Although individuals of Latino ethnicity are less likely to be up to date with CRC screening than Non-Latino whites,²⁵ we identified only 2 studies that have examined Latino attitudes toward specific screening tests.^26,27 Our study is the first to identify a specific association between Latino ethnicity and a preference for FOBT over colonoscopy. Reasons for this preference may involve social and cultural factors that are more prevalent within these populations, including concerns about modesty, fear of pain, and lack of perceived risk for a condition that would warrant an invasive procedure.²⁸

We are unaware of earlier studies that report an association between educational attainment and screening test preferences, although others have found that adults with lower educational attainment are more likely to prefer no screening at all.^18,21,26 We did not include a “no screening” option in our survey, but like Guerra et al., we did identify an association between lower educational attainment and poorer knowledge of key facts pertaining to CRC screening.²⁹ It is possible that patients may be more amenable to CRC screening in general and more interested in colonoscopy specifically, if they can be helped to understand that removing precancerous polyps reduces the risk of developing CRC and that most people with polyps and early-stage cancer do not have symptoms.

Consistent with prior studies,^18,20 respondents who selected colonoscopy volunteered test accuracy as the most important reason for their choice. Among those who preferred FOBT, most mentioned their desire for a test that is easy and convenient.²¹ Because test accuracy and ease/convenience comprised almost 75% of the explanations given for screening test preferences, it may be particularly important to emphasize these when discussing screening alternatives with patients. Otherwise, the most common explanations for choosing FOBT seemed to imply, at least on some level, a negative evaluation of colonoscopy—for example, that it is too costly, invasive, uncomfortable, time consuming, or indiscreet. Therefore, after describing colonoscopy either by itself or in conjunction with FOBT, decision making might be streamlined and enhanced by explicitly probing patients’ feelings about colonoscopy in terms of each of these domains.

Individuals with minimal or no health insurance typically have very high out-of-pocket costs for screening colonoscopy. Moreover, resources are frequently unavailable to offer this procedure in settings where these individuals receive health care. In the survey, we were unable to provide detailed information about the cost of colonoscopy for specific patient groups. As a probable consequence, whereas more than 40% of respondents had a Medicaid-type health plan or no insurance, only 7% cited cost as a key influence on their test preference. Thus, even if cost information were provided, it is likely that a majority of these respondents would prefer FOBT for reasons in addition to cost.

The largest proportion of respondents were between the ages of 40 and 49, coming due but not yet eligible for average-risk CRC screening. Whereas younger individuals may be less amenable to invasive tests, it is unclear when a shift in attitude might take place. We found, for example, that a slight majority of 50- to 64-year respondents also preferred FOBT over colonoscopy. Meanwhile, although two thirds of those more than age 65 preferred colonoscopy over FOBT, the total number of respondents in this category was relatively small.

Based on the above, future work should focus in at least 3 areas. First, better ways of presenting patients with CRC screening information are needed. We agree with the recommendation of Klabunde et al. that nonphysician members of the health care team should play a greater role in promoting CRC screening.³⁰ Medical assistants, for example, are likely to have more time to discuss screening alternatives with patients. Such discussions can also take place after patients have had a chance to consider written educational materials or decision aids. In this light, it is important to develop tailored strategies for unique populations as well as recognize which elements of knowledge make the greatest difference in encouraging screening.

Second, providers who wish to advocate for colonoscopy over other tests should know how to more effectively educate patients about its advantages, focusing in particular on its therapeutic effect and low required frequency. Nonetheless, they should recognize that many patients are unlikely to complete colonoscopy regardless of attempts at persuasion. For this group of patients, choices are especially important. In addition, offering an alternative to patients only if they refuse colonoscopy does not constitute genuine informed decision making because patients who do accept colonoscopy might have selected an alternative if a choice was made explicit from the beginning.

Finally, whereas it seems reasonable to assume that facilitating choice improves overall rates of CRC screening, this has yet to be established. Two randomized controlled trials have failed to show such an effect.^31,32 However, these were carried out in Italy and Australia where public attitudes toward CRC screening may be different than in the United States, and overall participation in screening was low because patients were recruited through mailed invitations rather than through discussions with PCPs. A cross-sectional study in a VA setting also failed to show that incorporating patient preferences was associated with greater receipt of preventive services.⁷ In fact, 1 study found that offering choices might result in lower rates of screening.³³ Giving patients too many options (and there are at least 5 in CRC screening) may be counterproductive because it produces decisional overload. Clearly, facilitating informed decision making and demonstrating that this increases overall rates of screening represent daunting challenges.

This study has important limitations. Survey items designed to assess screening test preferences and attitudes may not predict patients’ actual preferences and behavior when PCPs present them with choices or recommend a specific test.²¹ Similarly, decisions informed by a review of written information are not necessarily the same as those that would emerge during face-to-face conversations with PCPs. In fact, physician recommendation is consistently identified as 1 of the most important determinants of screening completion and the type of test employed.^27,29,34 Furthermore, because there was a forced choice for a screening test, those who would have preferred no screening or an option that is less invasive than colonoscopy are most likely to have been included in the FOBT group. Conversely, survey respondents—including younger ones who, in most cases, have not yet made real decisions about CRC screening—were able to consider more information and had more time to do so than is typically feasible during primary care visits, meaning their understanding of the 2 options was likely to have been closer to the ideal recommended by the USPSTF and other professional societies. In other words, they are more likely to have made an informed choice than is customary during primary care visits. Second, although we made every effort to present the characteristics of FOBT and colonoscopy in an accurate and objective manner, some may not agree that we adequately achieved this goal. Finally, like earlier studies focused on patients,^17–21 our study was not population based. Nonetheless, it is the first to demonstrate that respondents in a large and diverse community sample prefer an alternative to colonoscopy when given detailed information and a choice. Because we observed a consistently high rate of preference for FOBT over colonoscopy in all demographic subgroups, this increases the likelihood that our findings have broad applicability.