Although colorectal cancer (CRC) is the second leading cause of cancer death in the U.S., screening rates are low. Understanding the predictors of CRC screening is needed. In 2003, a random sample of patients aged 50 and over from three inner-city health centers was surveyed by computer-assisted telephone interview concerning CRC screening. The questionnaire was based on the Transtheoretical Model and the Theory of Reasoned Action. Factor analysis with Varimax rotation and logistic regression analyses were conducted. Of 319 surveys with data about endoscopy, 148 (46%) met guidelines (19 reported sigmoidoscopy within 5 years, 105 reported colonoscopy within 10 years, and 24 reported both within 5 years). Factor analysis identified three factors associated with increased likelihood of lower endoscopy within guidelines: Social Influence for CRC Screening (Eigenvalue 1.73), Barriers to Lower Endoscopy (Eigenvalue 2.00), and Lower Endoscopy Benefit/Ease (Eigenvalue 1.19). Variables in logistic regression associated with a lower rate of endoscopy include being African American (Odds Ratio (OR) = 0.35, 95% confidence interval = 0.13-0.96), being a current smoker (OR = 0.13, CI = 0.03-0.60), and having a higher score on the Barriers to Lower Endoscopy factor (i.e., viewed the inconvenience and unpleasant aspects as more troubling, OR = 0.33, CI = 0.18-0.60). The perceived inconvenience and unpleasant aspects of lower endoscopy are substantial barriers to screening. Advances in colon preparation procedures and better educational campaigns might lessen this perceived barrier and may be particularly important in disadvantaged and African American communities.