Canadian physicians’ choices for their own colon cancer screening du cancer du côlon SURVEY

choices for their own colon cancer screening. Can RESULTS: Of 2807 surveys, 46% were returned. Screening for CRC was reported by 53% of respondents. The Canadian Association of Radiologists members (61%) and the Canadian Association of Gastroenterology members (61%) were more likely to be screened than other specialties (P<0.01 and P<0.05, respectively). Members of the Society Obstetricians and Gynaecologists of (44%) were least likely to be screened (P<0.001). Men (P<0.001) and Ontario physicians (P<0.01) were more likely to be screened than women and Canadian physicians from other provinces, respectively. warrant screening (14%). DISCUSSION: More than one-half of all respondents were screened for CRC. Colonoscopy is the most common screening modality used. Lack of time is the most common reason cited for not participating in CRC screening.

In 2001, the Canadian Task Force for Preventive Health recommended the inclusion of FOBT or flexible sigmoidoscopy (FS) in the periodic health examination (6). In the recommendations for the periodic health examination, the Task Force concluded that there was insufficient evidence to include or exclude a colonoscopy.
The Canadian Association of Gastroenterology (CAG) published their most recent guidelines regarding CRC screening in February 2004 (7). In addition to biennial FOBT and FS every five years, they recommended colonoscopy every 10 years as an appropriate option for screening patients at average risk. Therefore, screening average risk patients may include annual or biennial FOBT, FS every five years, double contrast barium enema (DCBE) every five to 10 years or colonoscopy every 10 years.
There are no national estimates of CRC screening rates in Canada. It has been reported that 20% of eligible 50 to 59 year olds in Ontario, without CRC or inflammatory bowel disease, have undergone any one of the tests available for CRC screening (8,9). In the United States, recent national screening rates for any endoscopic modality have been reported at 48.1%, (range 30% to 64%) (10).
Our study aimed to determine how Canadian physicians are interpreting recommendations regarding CRC screening. We explored this by undertaking a survey examining personal preferences for CRC screening among target age Canadian specialists. Interspecialty, age, sex and geographical variables were examined. We also explored respondents' reasons for not participating in CRC screening.

METHODS
Membership mailing lists were requested from five professional societies, representing Canadian specialists, to facilitate a survey. The specialist groups were selected to reflect a broad range of physicians. The Canadian Society of Internal Medicine, the CAG, the Society of Obstetricians and Gynaecologists of Canada, the Canadian Psychiatric Association and the Canadian Association of Radiologists agreed to participate in the study.
A database of registered Canadian physicians older than 50 years was obtained from each organization (CAG excluded) and a 10 question survey was mailed along with a cover letter, consent information and a postage paid return envelope. The surveys were anonymous and colour coded to represent each specialty. The CAG database does not sort by age and, hence, the survey was mailed to all members. CAG members younger than 50 years were excluded from analysis of anything other than response rates.
The survey asked the physician whether they had undergone CRC screening and, if so, by which method. Respondents who had not been screened were asked to indicate their reason(s) from a list: • don't think there are sufficient data to warrant screening; • concerned about physical discomfort during endoscopy; • don't want to incur potential risks of endoscopy; • time constraints, but I am meaning to do it; • concerned about psychological distress during endoscopy; and • other.
All participants were asked about compliance with preventive health measures, specifically mammography, Papanicolaou smear, blood pressure monitoring, cholesterol monitoring and hepatitis vaccination. Those who indicated that they had pursued two or more of these measures were defined as compliers with preventive health care.
Each response was entered into a confidential database and results were analyzed by descriptive analysis. Statistical significance was determined by the χ 2 test.
The study was approved by the Research Ethics Board at the University of Manitoba, Faculty of Medicine (Winnipeg, Manitoba).

RESULTS
Of the 2807 surveys mailed out, 1291 were returned (46%) ( Table 1). Of 1291 respondents, 1075 (83%) were men. Thirty per cent of respondents were older than 65 years ( Table 2). Of 1291 respondents, 162 were younger than 50 years, and eight of 1291 did not return a complete survey. The remaining 1121 respondents were older than 50 years and constitute the survey sample.

Screening modality
Colonoscopy was the most common screening modality used (56%) and FOBT was the second most common modality (27%). Fewer than 15% of respondents used FS, DCBE or a combination of FS and FOBT as their initial modality. The questionnaire accounted for those who had a colonoscopy in response to a positive FOBT; hence, the colonoscopy rates represent only those who chose colonoscopy as their primary screening modality.

Region
The choice of initial screening modality also varied by province (

Screening interval
Of 335 respondents who had a screening colonoscopy, 305 (91%) would prefer to continue screening with this modality. Of those, 85% would choose to be rescreened in five years or sooner, and the remaining 15% would like to be screened at 10-year intervals.

Nonscreened respondents
Of the physicians who had not been screened for colon cancer and provided us with a reason as to why not (n=472), the most commonly cited reason (49%) was a lack of time with an intent to pursue screening in the future. Only 14% (159 of 1121) of all respondents thought there were not enough data to warrant screening (34% of the not screened group, 159 of 472). Other reasons for not being screened included physical discomfort (5%), concerns over complications at endoscopy (7%), that it had not been mentioned or recommended by their primary care physician (3%) or they had not given consideration to the issue (2%).

DISCUSSION
Our study shows that over one-half of Canadian specialists older than 50 years are undergoing CRC screening. Colonoscopy is the most common screening modality employed regardless of physician age, sex, specialty and region. Almost all physicians who underwent colonoscopic screening would prefer to continue using this modality for future screening and most would like to be rescreened at five year intervals or less.   Despite the recommendations of the Canadian Task Force for Preventive Health for FS as a first-line test for screening (6), fewer than 10% of screened Canadian specialists chose this modality, either alone or in combination with FOBT. Of those in the target age range who have not yet undergone screening, one-half cited a lack of time as their limitation and 77% of those would chose colonoscopy as their screening modality. A lack of evidence supporting screening was an uncommon reason for not participating.
Our study suggests that the screening rate among Canadian specialists in the target age range is higher than the rate reported in the literature for the general population (8,9). If respondents who cited "time constraints but I am meaning to do it" are considered, then 73% of Canadian specialists comply or intend to comply with CRC screening. This attitude toward screening is not limited to those specialists who arguably may have a heightened awareness of colon cancer, ie, gastroenterologists or radiologists, but crosses a wide spectrum of physicians.
In a recent survey of Alberta physicians, including family physicians, gastroenterologists and general surgeons, 58% stated that they recommend CRC screening to their average-risk patients older than 50 years (11). Although the overall rate mirrors our study's findings, only 26% recommended colonoscopy as the initial screening modality, whereas 79% recommended FOBT. It is important to emphasize that this study examined the primary care physician's recommendation to patients rather than the personal choice of specialists. These study variables likely explain the different results.
A weakness of our study is the lack of respondent stratification with respect to personal CRC risk. It is possible that respondents to this survey were a select group of individuals at higher than average risk for CRC. Thus, their choice of a colonoscopy as a first-line modality and selecting a screening interval of five years may reflect compliance with recommendations for high-risk patients. We speculate the effect of this potential factor to be small because physicians are not at increased risk of cancer.
It may be that the relatively high screening rates found in our study are a result of the greater likelihood that physicians who are compliant with screening recommendations would respond to surveys. Our survey tracked compliance with other health preventive measures (hepatitis and other vaccinations, breast and cervical cancer screening, blood pressure and lipid level determinations) and, indeed, a greater number of those undergoing CRC screening were compliers with preventive health care measures. Despite this, specialist uptake of CRC screening is very high compared with the general population. Variables such as sex and knowledge about CRC have been shown to be important among eligible adults in the United States (12,13) and may partly explain the high screening rate documented in the present study.
Of greater interest is that specialists seem to favour and pursue the most aggressive approach to CRC screening. Do they believe other screening strategies that are promoted to Canadians by the Canadian Task Force for Preventive Health to be inadequate? Why are they accessing resources that are scarce (7), and nonreimbursable in some jurisdictions, for average risk screening?
The Quebec Association of Gastroenterologists has recently responded to these challenging questions (14). The task force stated, with respect to the role of colonoscopy in CRC screening, that higher quality data are not forthcoming. Thus, a screening program with colonoscopy is called for with designated tariffs for reimbursement. The general public and primary caregiver in Quebec have been given clear directives on screening strategy. If provincial and national health authorities adopt the recommendations of the Quebec Association of Gastroenterologists, then policy will reflect what appears to be Canadian specialist practice for personal health care.

ACKNOWLEDGEMENTS:
The authors thank the national physician organizations whose collegial cooperation made this study possible. Dr Charles Bernstein is supported in part by a Canadian Institutes of Health Research Investigator Award and a Crohn's and Colitis Foundation of Canada Research Scientist Award. Dr Ilnyckyj is supported in part by AstraZeneca Canada.