Fig. 2

Sensitivity and positive predictive value of the 4 best single algorithms for classifying type 1 diabetes in the derivation cohort by age at diagnosis*, displayed with the proportion of all diabetes cases classified as type 1 using the reference standard (dashed line). Algorithms: (a) ratio of type 1 to type 2 codes ≥ 0.5; (b) ratio of type 1 to type 2 codes ≥ 4; (c) at least 1 insulin prescription within 90 days of diagnosis; (d) multiple daily injections with no other glucose-lowering medication prescriptions
*smoothed using 15-year moving averages