ADDITIONAL VALUE OF BIOCHEMICAL TESTS IN SUSPECTED ACUTE APPENDICITIS

Objective: To evaluate the efficacy of biochemical tests in diagnosing acute appendicitis. Design: Open prospective study. Setting: District hospital, Norway. Subjects: 257 patients with suspected acute appendi citis. Interventions: Initial diagnostic accuracy of a logistic regres sion model using available clinical data was compared with results of corresponding models that included an increasing number of inflammator y parameters. Main outcome measures: The estimated probabilities of ap pendicitis in different testing groups were analysed using receiver op erating characteristic (ROC) curves. Results: A model including only c linical variables had a mean area under the ROC curve of 0.854. When t he total white blood cell count, C-reactive protein concentration, and neutrophil count were added, the model improved significantly to 0.92 0. Conclusion: Biochemical tests are of additional value in a computer model, and the tests should, if used rationally, also provide physici ans with important information in the investigation of acute appendici tis.