A comprehensive computer-assisted diagnosis system of acquired and congenital pediatric diseases has been developed. In a pilot study, using patient information available at the time of the initial history and physical examination, the system included the correct diagnosis as part of a differential diagnosis in 90% of the cases. In those selected, the patient's final confirmed diagnosis had not been considered by the doctor on admission. Such a system can reduce the risk of overlooking a diagnosis as well as the time needed to make a diagnosis. It also permits the physician to have immediate access to newly described diagnoses. A medical secretary, using the vocabulary provided, can take the findings from a patient's chart and obtain the list of diagnoses from the system as accurately as a physician.