Evaluation of a national surveillance unit

Aim-The Australian Paediatric Surveillance Unit (APSU) facilitates national active surveillance of uncommon childhood conditions. This study assessed whether it fulfilled its objectives and satisfied criteria established by t he Centers for Disease Control and Prevention (CDC) for evaluating surveill ance systems. Methods-Anonymous questionnaires were sent to users of the system, individu al studies were reviewed, and data were collected from independent sources. Results-Seven hundred and sixty six clinicians, 48 investigators, and 15 pu blic health professionals responded to the questionnaires. Clinicians repor ted that the APSU was useful, 33% saying information provided by the APSU i nformed or changed their clinical practice. Most (88%) reported that comple ting monthly report cards was not a burden. Impact on policy development wa s limited by suboptimal dissemination of information to public health profe ssionals. Flexibility and timeliness were limited by design. Estimated sens itivity of APSU studies ranged from 92% (congenital rubella) to 31% (drowni ng/near drowning). Positive predictive value of notified cases was over 70% for most studies. Conclusion-The APSU fulfils most of its objectives and meets CDC criteria s alient to these. Ways in which the APSU could be improved have been identif ied, as have methodological challenges and limitations in applying CDC guid elines to this type of unit.