Female Gender and Other Factors Predictive of a Limited Screening Flexible Sigmoidoscopy Examination for Colorectal Cancer Mohamad A. Eloubeidi, M.D., M.H.S., Michael B. Wallace, M.D., M.P.H., Renee Desmond, Ph.D., and Francis A. Farraye, M.D., M.Sc. Division of Gastroenterology and Hepatology, and Medical Statistics Section, Department of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama; Medical University of South Carolina, Charleston, South Carolina; and Section of Gastroenterology, Boston Medical Center, Boston University School of Medicine, Boston, Massachusetts OBJECTIVE: Flexible sigmoidoscopy (FS) screening for colorectal cancer (CRC) is associated with reduced mortal- ity from CRC. It is unknown whether FS is equally effective in men and women, but differences in anatomy and percep- tion of pain may increase the difficulty of performing FS in women. The aim of this study was to determine factors associated with a shorter or limited screening FS. METHODS: Patients referred by their primary care provider were eligible for screening sigmoidoscopy if they were 50 yr or older with negative fecal occult blood tests and no first- degree relative with colorectal cancer at age 55 yr or younger. A detailed questionnaire regarding demographic characteristics and risk factors for CRC, aspirin and multi- vitamin use, and previous abdominal surgery was completed by the patient on a standardized form before their procedure. The histologic type (hyperplastic, adenoma, normal mucosa, or carcinoma) of each polyp was recorded. Depth of exam- ination (in cm) was recorded based on the standardized markings on the shaft of the sigmoidoscope when it was thought to be in a straight position. Limitations to the examination (angulation, pain, and poor preparation), other mucosal findings, and complications were also noted. RESULTS. A total of 3980 patients (52% female) were pro- spectively enrolled in a screening program over a 22-month period. Women were more likely than men to report previ- ous pelvic or abdominal surgery (OR = 2.64, 95% CI = 2.29 –3.05) and were less likely to have had a previous sigmoidoscopy (OR = 0.71, 95% CI = 0.61– 0.83). Females were almost twice as likely as males to have a procedure limited in some way (angulation, spasm, or pain) (OR = 1.86, 95% CI = 1.63–2.13). When defined by depth of examination, females were significantly more likely than males to have a procedure of 50 cm (OR = 1.93, 95% CI = 1.63, 2.29) and were less likely to have an adenomatous polyp or cancer detected (OR = 0.55, 95% CI = 0.42– 0.71). The average endoscopy distance for women was 52.3 cm, compared with 55.2 cm in men (p  0.0001), and the average number of polyps detected in women was 1.4, compared with 1.56 in men (p = 0.003) among patients with at least one polyp. Using multivariable analysis, females were more likely to have an examination of 50 cm com- pared with men, controlling for age, spasm or pain on examination, previous surgery, angulation of the colon, and type of endoscopist—MD or nonphysician endoscopist (OR = 1.67, 95% CI = 1.41–1.99). CONCLUSION. Women are more likely than men to have a shorter and more limited FS. This is partly owing to in- creased colonic angulation and pain during the examination. Methods aimed at reducing pain and improving maneuver- ability in an angulated colon during FS may improve the effectiveness of CRC screening in women. (Am J Gastro- enterol 2003;98:1634 –1639. © 2003 by Am. Coll. of Gas- troenterology) INTRODUCTION Colorectal cancer (CRC) is the third most common cancer in men and women. It is estimated by the American Cancer Society that there will be 148,300 cases in 2002, including 107,300 of colon cancer and 41,000 of rectal cancer (1). The American Cancer Society, the American College of Gastro- enterology, The National Cancer Institute, and the U.S. Preventive Services Task Force recommend flexible sig- moidoscopy (FS) screening in average-risk patients older than 50 yr as one of the options for CRC screening (2). Results from case– control studies showed that previous use of rigid sigmoidoscopy or flexible sigmoidoscopy was as- sociated with a 59 – 80% reduction in colorectal cancer mortality from cancers arising in the distal colon and rectum (3, 4). The protective effect of sigmoidoscopy lasted for 6 –10 yr after the examination. Despite this, the acceptance of FS has been limited. According to the Behavioral Risk Factor Surveillance System in 1997, 30.5% of respondents reported having undergone a flexible sigmoidoscopy within the preceding 5 yr (5), whereas 44% of respondents reported THE AMERICAN JOURNAL OF GASTROENTEROLOGY Vol. 98, No. 7, 2003 © 2003 by Am. Coll. of Gastroenterology ISSN 0002-9270/03/$30.00 Published by Elsevier Inc. doi:10.1016/S0002-9270(03)00255-7