[Competence of senior medical students in diagnosing tuberculosis based on chest X-rays]

To evaluate the competence of senior medical students in diagnosing tuberculosis (TB) based on their reading of chest X-rays, as well as to identify the factors associated with high scores for the overall interpretation of chest X-rays.

In October 2008, a convenience sample of senior medical students who had undergone formal training in radiology at the Federal University of Rio de Janeiro School of Medicine, in the city of Rio de Janeiro, Brazil, were invited to participate in the study. Six chest X-rays (three of TB patients and three of patients without TB) were selected. Participants were asked to choose one of the three probable radiological interpretations, and one of the four subsequent suitable clinical approaches. They also completed a questionnaire designed to collect data related to demographics, career of interest, time spent in emergency rooms and year of study. The sensitivity and specificity related to competence in the radiological diagnosis of TB, as well as a score for the overall interpretation of chest X-rays, were calculated.

The sensitivity of the probable radiological diagnosis of pulmonary TB, based on the three chest X-rays of patients with TB (minimal, moderate and extensive) was 86.5%, 90.4% and 94.2%, respectively, and the specificity was 90%, 82% and 42%. The only factor associated with a high score for the overall radiological interpretation was the year of study.

In this sample of medical students, who had received formal training in radiology early in their medical school course, the competence in interpreting the chest X-rays of TB patients was good. The year of study seems to influence overall chest X-ray reading skill.