Reza Omidvar in the RECORDER team has created a Population Denominator web app that is available for all researchers to use in their work.

This dashboard provides population denominators for the population of England from 2006 onwards, stratified by sex, age and index of multiple deprivation (IMD). The data is based on the Office for National Statistics (ONS) mid-year population estimates. The results are modifiable to any combination of calendar year, 1 year age band, sex and IMD quintile or decile and can be downloaded.

The population denominators are used by the RECORDER team when they calculate incidence and prevalence rates for rare diseases. After identifying everyone in England with a rare disease they divide this number by the denominator to create a rate. This enables exploration of the effect of age, sex and IMD on the rate.