PURPOSE: Pulmonary embolism (PE), an elusive diagnosis, is detected by a diagnostic work-up that is often guided by the physician's level of clinical suspicion. The ability to accurately assess PE risk on solely clinical grounds may increase with the physician's level of training. This study documented the ability of house staff practicing in an academic teaching hospital to accurately assess the clinical likelihood of PE in patients.
METHOD: During a seven-month period, all 245 patients with suspected acute PE who had had lung scans ordered via a computerized order-entry system were enrolled in the study. When ordering the lung scans, all physicians (interns, residents, and attending physicians) were required to also enter their levels of clinical suspicion on a scale of 0 to 100. The physicians' levels of clinical suspicion were correlated with the final determinations of PE, and receiver operating characteristic (ROC) curves were calculated for patients' and physicians' subgroups.
RESULTS: Attending physicians were most able to diagnose PE; residents were moderately able to make the diagnosis, and interns were least able to diagnose PE. The area under the ROC curve for a correct identification of patients with PE was greatest for attending physicians (0.839), intermediate for residents (0.601), and least for interns (0.594).
CONCLUSION: The ability to correctly assess a patient's likelihood of PE increases with a physician's level of training, suggesting that more senior physicians should be involved in the diagnostic work-up of patients with suspected acute PE. More instruction may help medical students, interns, and residents navigate clinical scenarios in which the diagnosis is uncertain or in which sequential tests must be performed to reach the correct diagnosis.