An evaluation of the accuracy of clinical diagnosis at admission in a population with epidemic meningococcal disease.

The accuracy (sensitivity and positive predictive value) of the clinical diagnosis given by the general practitioner before admission to hospital was evaluated retrospectively in a population with epidemic meningococcal disease. The study population consisted of approximately 32,000 subjects. In a 12-year period, 344 patients were discharged from hospital with CNS infections, 274 of whom were admitted with a diagnosis suspecting a CNS infection. A further 401 patients were admitted with suspicion for, but discharged without a CNS infection. Overall, the sensitivity was 79.7% and the positive predictive value was 40.6%. There were no significant changes in the accuracy during the study. The sensitivity differed significantly between the age groups (P less than 0.001) and was lowest among the adults (15+ years, 67.9%) and the 0-2-year-old children (72.7%). Also among the 0-2 year-olds, the positive predictive value was low (34.1%) and not significant, indicating that it was more difficult to obtain the correct clinical diagnosis in this group.