The Institute of Public Health in Ireland publishes estimates and forecasts of the prevalence of chronic health conditions for national and subnational areas on the island of Ireland. The estimates and forecasts are based on statistical models of nationally representative health survey data that estimate the risk of having the condition. The risks of having the condition are then applied to population estimates and projections. 

The purpose of this document is to: 

1. Compare IPH prevalence estimates with prevalence estimates from other health surveys on the island (see Table 1). 

2. Highlight the methodological issues in comparing prevalence estimates from different surveys (see Box 1).