RESUMEN
PURPOSE: Studies suggest time pressure has negative effects on physicians' working conditions and may lead to suboptimal patient care and medical errors. Experimental evidence supporting this is lacking, however. This study investigated the effect of time pressure on diagnostic accuracy. METHOD: In 2013, senior internal medicine residents at three hospitals in Saudi Arabia were divided randomly into two groups: a time-pressure condition and a control condition without time pressure. Both groups diagnosed eight written clinical cases presented on computers. In the time-pressure condition, after completing each case, participants received information that they were behind schedule. Response time was recorded, and diagnostic accuracy was scored. RESULTS: The 23 participants in the time-pressure condition spent significantly less time diagnosing the cases (mean = 96.00 seconds) than the 19 control participants (mean = 151.97 seconds) (P < .001). Participants under time pressure had a significantly lower diagnostic accuracy score (mean = 0.33; 95% CI, 0.23-0.43) than participants without time pressure (mean = 0.51; 95% CI, 0.42-0.60) (F[1, 41] = 6.90, P = .012, η = 0.15). This suggests participants in the time-pressure condition made on average 37% more errors than control participants. CONCLUSIONS: Time pressure has a negative impact on diagnostic performance. The authors propose that the effect of time pressure on diagnostic accuracy is moderated by both the case difficulty level and the physician's level of experience. Post hoc analyses demonstrated that time pressure affects diagnostic accuracy only if cases are not too difficult and physicians' expertise level is intermediate.