ESTIMATING THE PROBABILITY OF ACUTE APPENDICITIS USING CLINICAL-CRITERIA OF A STRUCTURED RECORD SHEET - THE PHYSICIAN AGAINST THE COMPUTER

Objective: To evaluate physicians' probability estimates of acute appe ndicitis based on structured collection of clinical data. Design: Open prospective study. Setting: District hospital, Norway. Subjects: 304 patients admitted with suspected acute appendicitis. Interventions: In itial diagnostic accuracy of physicians was compared with correspondin g results from a computer model. Main outcome measures: The estimated probabilities of appendicitis in different testing groups were analyse d using receiver operating characteristic (ROC) curves. Results: Physi cians' estimates had a mean area under ROC-curve of 0.81 (95% CI 0.79 to 0.82), not significantly different from the computer model. Both co rrelated well with the actual rate of appendicitis, but the physicians tended to overestimate the probability by 10%. Conclusion: Physicians ' probability estimates perform rather well. Further attempts to imple ment a probabilistic approach in the diagnostic process of acute appen dicitis therefore seem justified.