Gschwend et al. [16], who used the IMS CORE Diabetes Model to estimate the cost effectiveness of insulin detemir compared with NPH insulin in patients with type 1 diabetes using data from a 2-year randomised controlled trial, showed that results were highly sensitive to the event rate used with small differences in the rate causing detemir to lose dominancy over NPH. This evidence concerns the gene INS and type 1 diabetes mellitus.