Overview

Objectives
The aim of this project was to develop a data tool to be widely used in studies of population, by generating a time series database of survey demographic histories and ancillary information from the General Household Survey (GHS). The main objective of developing such a tool was to enable investigation of fertility and partnership trends over several decades in Britain. Merging annual GHS datasets from 1979 onwards, the study looked to encompass information on socio-economical characteristics of individuals, their current family situation and also their past childbearing and partnership history.

Methods
Using advanced programming, data management and data cleaning, a time series database of the GHS from 1979-2009 was created from 29 annual survey rounds. It included substantial parts of the demographic histories –fertility and partnership—collected in the Family Information section of the survey, together with ancillary information. This required a considerable investment of time in creating variables that were consistent over time and in identifying and, in some cases, correcting defective data. A new consistent set of survey weights for the entire time series was also created.

Findings
The time series database was produced successfully and was used for a variety of papers on fertility and partnership. Analysis using the data tool gave a deep insight into trends in fertility over the last two decades linked with economic and societal changes. The individual data could also be used to understand more general aggregate changes.

During the research, however, serious errors were found in the GHS fertility histories. The research identified the principal source of these errors and a method of correcting them to a substantial extent was developed. As a result, a new set of survey weights was produced for the GHS 1979-2009, both for household analysis and for individual analysis of the Family Information section.

The Office for National Statistics (ONS) had been aware of the deficiencies of the GHS fertility histories, but had not been able to identify the source of the error. This research identified why the errors were occurring in the GHS fertility histories and, as a result, ONS amended their survey procedures to try to avoid this source of error.

In addition, the database is to be deposited in the Data Archive and will be a valuable resource for further work on fertility and partnership in Britain, as well as on households and a range of other social and demographic topics.