Purpose: To erform a process analysis of missed and delayed diagnoses of breast and colorectal cancers to identify: (1) the cognitive and logistical factors that lead to these diagnostic errors, and (2) prevention strategies.
Methods: Using 56 cases (43 breast, 13 colon) of missed and delayed diagnosis, we performed structured analyses to identify specific points in the diagnostic process in which errors occurred. Each error was classified as either a cognitive error or logistical breakdown. Finally, two physician-investigators identified strategies to prevent the errors in each case.
Results: Virtually all cases involved one or more cognitive errors (53/56, 95 %) and approximately half (31/56, 55 %) involved logistical breakdowns. The clinical activity most prone to cognitive error was the selection of the diagnostic strategy, both during the office visit (25/56, 45 %) and during interpretation of test results (22/50, 44 %). Arrangement of follow-up visits with a primary care physician (8/29, 28 %) or specialist physician (7/29, 26 %) were especially prone to logistical breakdowns. Adherence to current clinical guidelines could have prevented at least one error in 66 % of cases and assistance from a patient advocate could have prevented at least one error in 48 % of cases.
Conclusions: Cognitive errors and logistical breakdowns are common among missed and delayed diagnoses of breast and colorectal cancers. Prevention strategies should focus on ensuring improving the effectiveness and use of clinical guidelines in the selection of diagnostic strategy, both during office visits and when interpreting test results. Tools to facilitate communication and to ensure that follow-up visits occur should also be considered.