The evidence based clinician: part 5 - applying evidence to your patient
In the final part of this series, Christopher Ball explains how to apply evidence about prognosis to your patient
Many clinical decisions depend on doctors making predictions about the likely consequences of diseases on patients. Unfortunately, risk can be difficult to understand --people and governments often behave illogically in response to perceived risk. Extremely rare conditions like variant Creutzfeldt-Jakob disease led to uproar in the media and to the government spending billions of pounds. Yet common causes of death among young people--for example, road crashes--are relatively ignored and underfunded.
Prognostic studies rarely help because they typically use complex statistical analysis to identify the relevant risk factors and then present multiple factors using numbers that do not seem to relate closely to patients' outcomes. Worse still, as we shall see, these numbers are difficult to manipulate or customise.
Integrating prognostic information into clinical care requires care and an understanding of your patient's ideas and concerns. Everyone likes certainty, and patients often have false expectations that doctors can divine the future.