Biasing Influence of 'Mental Shortcuts' on Diagnostic Decision-Making: Radiologists Can Overlook Breast Cancer in Mammograms When Prior Diagnostic Information Is Available

• Published in: Diagnostics (Basel) Vol. 12; no. 1; p. 105
• Main Authors: Branch, Fallon, Santana, Isabella, Hegdé, Jay
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 04.01.2022; MDPI
• Subjects: anchoring and adjustment; Bias; Breast cancer; Brief Report; Clinical decision making; cognitive rules of thumb; Data collection; diagnostic radiology; Heuristic; heuristics; judgement; Mammography; Probability; Software; judgement; cognitive rules of thumb; heuristics; medical error; bias; screening mammography; diagnostic radiology; anchoring and adjustment
• ISSN: 2075-4418; 2075-4418
• DOI: 10.3390/diagnostics12010105

When making decisions under uncertainty, people in all walks of life, including highly trained medical professionals, tend to resort to using 'mental shortcuts', or heuristics. Anchoring-and-adjustment (AAA) is a well-known heuristic in which subjects reach a judgment by starting from an initial internal judgment ('anchored position') based on available external information ('anchoring information') and adjusting it until they are satisfied. We studied the effects of the AAA heuristic during diagnostic decision-making in mammography. We provided practicing radiologists ( = 27 across two studies) a random number that we told them was the estimate of a previous radiologist of the probability that a mammogram they were about to see was positive for breast cancer. We then showed them the actual mammogram. We found that the radiologists' own estimates of cancer in the mammogram reflected the random information they were provided and ignored the actual evidence in the mammogram. However, when the heuristic information was not provided, the same radiologists detected breast cancer in the same set of mammograms highly accurately, indicating that the effect was solely attributable to the availability of heuristic information. Thus, the effects of the AAA heuristic can sometimes be so strong as to override the actual clinical evidence in diagnostic tasks.