Fifteen years ago, computer-aided diagnosis of the acute abdomen promised much. Today it is little used. Studies have been flowed by poor trial design, bias, selective reporting of results, statistical naivety and spurious conclusions. The computer system lacks 'common sense' and is less accurate than clinicians. Yet its introduction has been associated with improved patient management and outcome. Much of the effect arises from structured data collection methods and some from audit feedback to clinicians. It is on these innovations, not on the computer, that future work should focus.