Preexamination prediction of radiographic findings.

Computerized medical logic has been developed to calculate the patient-specific pretest likelihood of pleural fluid for radiographic examinations. This medical logic was determined by searching the computerized data base for clinical indicants which are found to differ between groups of patients with and without pleural fluid. By using a priori probabilities of pleural fluid and sequential application of Bayes' equation to revise the likelihood according to the presence of significant indicants, patient-specific likelihood were calculated. This medical logic was tested on a group of 591 patients with and without pleural fluid by radiographic evidence. The results indicated a sensitivity of 95% and a specificity of 81%.