The fact that physicians might not always offer an intervention known to save lives is nothing new. Knowledge is the awareness of new evidence or practice guidelines, and acceptance is agreement that the proposed policy represents good care. Ability involves having the time and resources to implement change, and reinforcement entails the use of reminder systems and other measures that maintain the practice over time. This framework helps to explain clinicians' disaffection with colorectal cancer screening. The first barrier is lack of knowledge.
Many physicians are unfamiliar with the evidence that screening reduces mortality.
Furthermore, physicians may not know the current protocols for screening. Many assume that guaiac testing in the office, performed on the glove used in a rectal examination, constitutes fecal occult blood testing. Finally, physicians may not know which types of polyps are premalignant or, having detected polyps on endoscopy or barium enema, which sizes require biopsy. The next barrier is attitudinal. Physicians can know the facts about colorectal cancer screening but remain uneager to act.