Prostate cancer risk stratification: to biopsy or not to biopsy?

Risk calculators (Clinical Prediction Models) have been in use within medicine for quite some time. A risk calculator is essentially a model, which takes a patient’s risk factors, combines them all into an equation and assigns a level of risk. Risk calculators can be used to predict any outcome, be that success of a surgical procedure (1) or prognosis following an acute myocardial infarction (2). The level of risk can then be quantified as a percentage. In this way, risk calculators offer a logical and systematic approach to the use of patient risk factors, which can then be used to influence clinical decision-making.