Can administrative health utilisation data provide an accurate diabetes prevalence estimate for a geographical region?

•Administrative health service utilisation data can be used to estimate diabetes prevalence at a population level.•The study optimises an algorithm to estimate diabetes prevalence using administrative data.•At an individual level, the use of diabetes-related services may not be a good proxy of a clinical diagnosis of diabetes.•This study highlights the potential value of a register constructed from both laboratory results and administrative data.