Abstract B112: Relationship of colorectal cancer awareness and knowledge with colorectal cancer screening: results of a population-based study
Authors: Brandt Heather M. , Ranhofer Heather , Sharpe Patricia A. , Hardin James W. 
Published: December 2010

Purpose: Participation in colorectal cancer (CRC) screening lags behind screening for other types of cancer despite the ability to prevent the development of CRC and down-stage disease. The purpose was to describe the association of CRC awareness and knowledge with CRC screening.

Methods: Trained interviewers from a professional survey firm conducted computer-assisted, random digit dialed telephone interviews, with landline and cell phone numbers, using a 144-item instrument developed via literature review, expert panel review, and pretesting. South Carolina residents aged 45-75 years were contacted. For this paper, analysis was restricted to respondents aged 50-75 (n=1,302) who fall in the recommended screening age range and answered knowledge, awareness, and screening items. Data were analyzed with SAS and STATA. Odds ratios were adjusted for race and gender.

Results: Respondents (n=1,503) were mostly female (63%), EA (77%), had at least some college education (59%), had household income of less than $49,999 (48%), married or lived with a partner (62%), had health insurance (91%), and unemployed/not working (57.1%). Mean age was 60.3 years (SD=8.6).

A majority of respondents had heard of CRC (91%). Of those who had heard of CRC, the majority had heard of CRC screening (96%). More than half of respondents (69%) could name any of the CRC screening tests. The most common CRC screening test named was colonoscopy (90%). Respondents who had heard of a CRC had greater odds of having had any CRC screening test (aOR=1.71; CI: 1.06-2.76; p&lt;0.028) and colonoscopy (aOR=1.59; CI: 1.03-2.45; p&lt;0.034) than those who had not heard. Respondents who could correctly name at least one CRC screening test had greater odds of having had any CRC screening test (aOR=3.74; CI: 2.76-5.08; p&lt;0.001) and colonoscopy (aOR=3.69; CI: 2.83-4.82; p&lt;0.001) than those who could not name a test. A CRC awareness index score (range 0-4) was created by assigning a +1 to each of four awareness items. A one-unit increase in the awareness score significantly increased respondents being more likely to have had CRC screening test (aOR=1.44; CI: 1.30-1.59; p&lt;0.001), colonoscopy (aOR=1.43; CI: 1.29-1.57; p&lt;0.001), flex sigmoidoscopy (aOR=1.27; CI: 1.13-1.41; p&lt;0.001), or FOBT (aOR=1.13; CI: 1.02-1.25; p&lt;0.016). The CRC knowledge item answered correctly most often was “colon cancer can start as a polyp, which is a small growth found in the colon” (97%) and least often was “colon cancer is most often caused by a person's behavior or lifestyle” (26%). A CRC knowledge index score (range=0-14) represented total number of correct responses. A one unit increase in knowledge score significantly increased respondents being more likely to have had any CRC screening test (aOR=1.05; CI: 1.02-1.10; p&lt;0.004), colonoscopy (aOR=1.05; CI: 1.02-1.09; p&lt;0.004), or FOBT (aOR=1.04, CI: 1.00-1.07; p=0.043). There were also statistically significant differences by race and gender.

Conclusion: Generally, there were high levels of awareness and knowledge scores, but modest participation in CRC screening. Higher levels of awareness and knowledge showed increased likelihood of CRC screening, yet CRC screening rates continue to be lower pointing to the need for interventions in addition to those focused on awareness and knowledge to improve adherence to recommended screening guidelines and reduced CRC cases.

Citation Information: Cancer Epidemiol Biomarkers Prev 2010;19(10 Suppl):B112.