more limited than for prospective studies with incident cases of disease. Those prospective studies that have previously evaluated the performance of genetic markers have been set outside the UK, typed fewer type 2 diabetes risk alleles, or reported only some of a range of metrics available to evaluate the performance of a predictive test (table 6).35 40 41 42 In a prospective study set in the UK, we therefore tested the performance of a panel of 20 common genes associated with type 2 diabetes, each of which confers a small to moderate increase in the risk of type 2 diabetes, and compared prediction based on genetic information alone, phenotypic information alone, and both, by using a range of metrics to assess predictive performance.
