Use of colonoscopy for colorectal cancer screening: Evidence from the 2000 National Health Interview Survey

Background: The use of colonoscopy as a primary screening tool for colorectal cancer is gaining momentum owing to several studies suggesting superior effectiveness and the recent, favorable decision by Medicare to cover all routine screening colonoscopies. This study documents the use of colonoscopy versus other tests to screen for colorectal cancer. Materials and Methods: Data from the 2000 National Health Interview Survey were analyzed. Fecal occult blood test (FOBT), sigmoidoscopy, and colonoscopy done for any reason and for routine screening only were analyzed for those greater than or equal to50 years without previously diagnosed colorectal cancer (n = 12,505). Results: The proportion of the total eligible population receiving any of the recommended tests for all possible reasons and for screening purposes only is 34.6% and 25.1%, respectively. For routine screening purposes, the test most commonly utilized was FOBT (55.6%) followed by colonoscopy (29.1%) and sigmoidoscopy (15.3%). When usage was assessed for all reasons, FOBT was still most commonly utilized (45.8%) followed by colonoscopy (38.7%) and sigmoidoscopy (15.5%). The elderly, non-White males and those with private insurance have a higher probability of receiving colonoscopy than FOBT. Several regional differences exist, including higher probability of undergoing sigmoidoscopy versus colonoscopy in the West. Conclusions: Only one fourth (upper limit one third) of the study population complied with colorectal cancer screening recommendations. Nearly one third of the routine screening tests done in 2000 were colonoscopies. This study provides baseline values that can be used to project future colonoscopy demand and identify potential supply barriers.