Using the Longitudinal Study database with Stata

Abstract

The Office for National Statistics Longitudinal Study (ONS/LS) is a huge, well maintained, database of linked census records for 1% of the population of England and Wales. With the imminent addition of 2001 census records it provides longitudinal data o n nearly a million people over a 30-year period. Although a wealth of research has flowed out of the LS since the mid-1970's it is probably still under-utilised, given its potential. This may be due to non-awareness of the richness of the dataset, or because it has a reputation of being "difficult" to work with. Access to the LS is indeed not so straightforward as some other studies but an academic support team is available to academic users free of charge and this takes much of the drudge out of access, as well as providing very constructive support for projects. The support team use Stata as the software medium of choice and academic Stata users will therefore find the interchange of code between themselves and the support team familiar. Procedures common to Stata users, such as stsetting and stsplitting longitudinal data, are now in common use for LS data. Release of LS data from ONS is subject to certain restrictions and these will be explained using an example of survival analysis following diagnosis of cancer.