Introduction

The Northern Ireland Longitudinal Study (NILS) is a large-scale data linkage study which has been created by linking administrative and statistical data.  The Study is designed for statistical and research uses only and is managed under Census legislation. Information is linked over time on people from Census, vital events and health registration datasets.  Data sources include 2001 Census data, birth and death registrations and demographic data derived from health registrations.

A Longitudinal Study has been successfully running in England and Wales since the 1971 Census. The England and Wales Longitudinal Study (LS) was designed as a sample around 500,000 people from the England and Wales population.  A similar study, the SLS, is also running in Scotland with a sample of nearly 300,000 people from the Scottish population.

NILS members are selected on 104 annual birth dates. In total around 500,000 people are included in the Northern Ireland Longitudinal Study. The Study will be of interest to a wide variety of researchers.  Information on using the NILS is provided in this website.