Why do we need longitudinal survey data?

Knowing people’s history helps in understanding their present state and where they are heading

University College London, UK

one-pager full article

Elevator pitch

Information from longitudinal surveys transforms snapshots of a given moment into something with a time dimension. It illuminates patterns of events within an individual’s life and records mobility and immobility between older and younger generations. It can track the different pathways of men and women and people of diverse socio-economic background through the life course. It can join up data on aspects of a person’s life, health, education, family, and employment and show how these domains affect one another. It is ideal for bridging the different silos of policies that affect people’s lives.

Work experiences of men and women explain
                        little of the gap in their hourly pay in the UK

Key findings

Pros

Longitudinal surveys form a record of continuities and transitions of a life as they happen, information not reliably gained through recollection or cross-section surveys.

Such surveys can reveal how domains of life intertwine over time in the same person.

Information from an individual’s past helps unpack present observations and future expectations for that person.

Multiple applications and an ability to link to administrative data make longitudinal surveys cost-effective.

Analyses of such survey data may detect causation within correlation.

Cons

Longitudinal survey data are expensive to collect and challenging to analyze.

Data must be collected over a long timeframe to show relevant, long-term results.

Having usable longitudinal survey data requires that informants not drop out of the survey, which limits how much information they can be asked to provide.

Data confidentiality has to be safeguarded, putting hurdles across easy research access.

Caution is needed in inferring causality from observational data, where changes may not be independently generated.

Author's main message

The rich data from longitudinal surveys can illuminate patterns and drivers of change within a lifetime and across generations. Data collected on the same individuals over time can relate outcomes at one time to information on the past and record interdependence among domains, such as health, wealth, and education. The dynamic perspective on linked developments in work and family roles can guide policy by revealing, for example, converging patterns in men’s and women’s lives and trends in social inequalities in life chances. Longitudinal surveys can inform policy in many arenas, making it important to find ways to finance and sustain them.

Full citation

Full citation

Data source(s)

Data type(s)

Method(s)

Countries