Last week I attended a conference on longitudinal research, focused on the factors across the life course that contribute to healthy ageing. What struck me was how potentially useful these studies could be for charities to understand the impact of their work, particularly in the long term.
Usually, untangling cause and effect in social research is a tricky business. But just pick up a packet of cigarettes*, and you will find one of several unambiguous health warnings, such as:
Smoking when pregnant harms your baby.
This is not just a statement designed to shock; it is something on which we have some pretty incontrovertible evidence: children born to mothers who smoke heavily during pregnancy have poorer health and reduced height and weight, as well as worse English and maths scores at 16 years old.
We know this—particularly the long-term consequences of maternal smoking during pregnancy—with such certainty thanks to 17,000 people born in Britain during one week in 1958. These people, who turn 52 this year, are part of the National Child Development Study (NCDS), which aims to track a cohort of babies ‘from the cradle to the grave’.
Longitudinal studies such as the NCDS are gold mines of evidence because the same individuals are observed over time, which allows for some indication of cause and effect. For this reason, they often influence social policy. For example, the UK government’s emphasis during the recent recession on getting unemployed young people into jobs is in response to findings from the 1970 British Cohort Study (BCS70), showing the long-term negative consequences of being out of education, employment or training as a young person.
Incidentally, we also used these findings in our report on the issue last year to demonstrate the value of charities such as Fairbridge intervening to help young people develop the skills necessary for work.
But how useful would longitudinal studies be to charities? NPC’s Measurement team are itching to do some analysis of longitudinal data, so if you have an interesting research question (check out this website if you want to find out what sorts of topics are covered by the longitudinal studies), get in touch.
*Well, last year: from October 2009 cigarette packets must contain picture warnings.