Towards safer diagnosis in clinical practice - understanding and using diagnostic tests in the neonatal unit more appropriately

The diagnostic process is a complex task that is more often than not done inherently by clinicians. However, it is in fact based around quantitative risk assessment and, as a result, when done intuitively is open to a significant risk of bias. By adopting a more structured and quantitative approach to diagnosis, clinicians might be in a position to make better diagnostic decisions. To achieve this, explicit recognition about the uncertainty surrounding diagnosis and knowledge about the basic properties of diagnostic tests, including disease incidence and predictive values, is necessary, as well as some consideration of newer concepts such as 'action thresholds'. Examples from everyday neonatal practice illustrate the potential clinical risks associated with the inappropriate use and interpretation of diagnostic tests and the potential benefits of approaching diagnosis in a more robust manner. A number of tools are now readily available to help clinicians move towards more 'evidence-based' diagnosis.