Potential unmet need for gout diagnosis and treatment: capture–recapture analysis of a national administrative dataset
Jackson G et al. – Capture–recapture analysis of administrative datasets provides a readily available method for estimating an aspect of unmet need in the population—in this instance potentially 20% of those with gout not being identified and treated specifically for this condition.Methods
- Hospitalization and drug dispensing claims (allopurinol or colchicine) data for all Aotearoa New Zealand were used to estimate the prevalence of gout in 2009 (n = 4295296).
- As a comparison, the authors calculated gout prevalence using a large primary care dataset using general practitioner diagnosis and prescribing records (n = 555313).
- For each of these datasets, they estimated the undercount through capture–recapture analysis using a Poisson regression model.
- A two-list model was used, which included covariates such as age, gender, ethnic groups and NZ deprivation quintiles.
- The crude prevalence of diagnosed gout in the Aotearoa New Zealand population aged ≥20 years was 3.75%.
- The covariate-adjusted capture–recapture estimate of those not recorded but likely to have gout was 0.92%, giving an overall estimated prevalence of 4.67% (95% CI 4.49, 4.90%) for the population aged ≥20 years.
- This amounts to 80% of people with gout being identified by the algorithm for the Aotearoa New Zealand data-that is being recorded in either lists of dispensing of allopurinol or colchicine or hospital discharge.
- After capture–recapture, gout prevalence for all males aged ≥20 years was 7.3% and in older (≥65 years) Maori and Pacific men was >30%.