Predictors of diagnostic accuracy and safe management in difficult diagnostic problems in family medicine.

OBJECTIVE: To investigate the role of information gathering and clinical experience on the diagnosis and management of difficult diagnostic problems in family medicine.
METHOD: Seven diagnostic scenarios including 1 to 4 predetermined features of difficulty were constructed and presented on a computer to 84 physicians: 21 residents in family medicine, 21 family physicians with 1 to 3 y in practice, and 42 family physicians with >or=10 y in practice. Following the Active Information Search process tracing approach, participants were initially presented with a patient description and presenting complaint and were subsequently able to request further information to diagnose and manage the patient. Evidence-based scoring criteria for information gathering, diagnosis, and management were derived from the literature and a separate study of expert opinion.
RESULTS: Rates of misdiagnosis were in accordance with the number of features of difficulty. Seventy-eight percent of incorrect diagnoses were followed by inappropriate management and 92% of correct diagnoses by appropriate management. Number of critical cues requested (cues diagnostic of any relevant differential diagnoses in a scenario) was a significant predictor of accuracy in 6 scenarios: 1 additional critical cue increased the odds of obtaining the correct diagnosis by between 1.3 (95% confidence interval [CI], 1.0-1.8) and 7.5 (95% CI, 3.2- 17.7), depending on the scenario. No effect of experience was detected on either diagnostic accuracy or management. Residents requested significantly more cues than experienced family physicians did.
CONCLUSIONS: Supporting the gathering of critical information has the potential to improve the diagnosis and management of difficult problems in family medicine.