The undercount of adults aged ≥20 years diagnosed with gout in New Zealand was estimated using capture-recapture analysis of administrative data sets. The crude prevalence of diagnosed gout in 2009 was 3.75% based on hospitalisation and drug dispensing claims for allopurinol or colchicines. The covariate-adjusted capture-recapture estimate of those not recorded but likely to have gout was 0.92%, giving an overall estimated prevalence of gout of 4.67% (95% CI 4.49 to 4.90%). The undercount of gout diagnoses is therefore about 20% and represents ‘an aspect of unmet need in the population.’ After capture-recapture, gout prevalence for all males aged ≥20 years was 7.3% compared with a prevalence of >30% in Māori and Pacific men ≥65 years. The authors concluded that undiagnosed patients need to be identified and treated specifically for gout.
