Jean Golding oversees a project to chart the lives of
a county's youngsters. Geoff Watts reports
In the past month, infant school teachers in the Avon area of southwest England have been receiving questionnaires about many of the seven-year-olds in their classes. The ten or so pages ask about each child's behaviour and abilities. Nothing unusual about that, you may think. Probably another Ofsted scheme seeking more ammunition for use against the poor teachers.
In fact the questionnaires represent the current phase of a continuing project called the Avon Longitudinal Study of Pregnancy and Childhood. Alspac is a potential gold-mine of data about health and development during childhood, and possibly beyond it. And "beyond" is precisely where Professor Jean Golding, the tireless godmother of the venture, intends it to go - so long as the struggle to keep the show on the road financially does not tempt her to throw in the towel.
The Alspac formula is so simple that you first wonder why no one began something like it decades ago. The idea is to record as much data as possible about the lives, environment and health of a cohort of children, and then look for clues to explain why some thrive mentally and physically while others do not. The more data recorded, the greater the variety of hypotheses that can be tested, and the higher the chances that new correlations will emerge.
Not everyone approves of such data-fishing expeditions. But it is the logistical rather than the theoretical hurdles that explain that while there have been previous longitudinal studies, no previous researcher has had the courage to embark on a scheme of this size.
Professor Golding, an epidemiologist in Bristol University's institute of child health, dreamed up Alspac in 1985. Having recognised the need to account for the ups and downs of child health, she devised a scheme for tracking all 14,000 children born in Avon between April 1991 and December 1992.
The cohort would be studied not just from birth but from conception, and through until they were pensioners.
"We used to say until they were seven," she says. "But we've put a nought on that figure now."
The geographical boundaries of her study follow the ghostly outline of governing bodies that no longer exist. "When we started, our study area was defined by the bit of the county of Avon that was within the South West Regional Health Authority. Both the county and the authority have now vanished. Our area used to be covered by one educational authority; now it has four."
The more Professor Golding says about the scheme, the more you find yourself admiring her for having had the nerve to undertake it. After following the mothers-to-be through pregnancy, the researchers began to collect data on the children themselves. During the early years, their mothers filled in detailed quarterly questionnaires on everything that might plausibly affect present and future health and well-being.
By way of checking on the quality of the data, Alspac staff saw a sample of 10 per cent of the children every four months for the first year, and every six months thereafter.
Now aged seven, all the children are being seen individually by a platoon of specialists who spend half a day successively sampling their blood, examining their vision and hearing, assessing their co-ordination, testing them for allergies, and much else.
When they are eight the children will be seen again, this time for a half day of psychometric testing. They will be checked once more before they leave their primary school, and then after they have begun secondary education. In addition to this, Alspac has access to their medical records. And with a year of schooling under their belts, their teachers are now being asked to contribute.
Alspac is progressively taking over Hampton House, the sometime site of Bristol's homeopathic hospital. The house has grounds with trees and grass - just what is needed to encourage parents to bring their children along, which they mostly do. The study has wide public support.
The woman who manages the programme of testing - 32 children each day for four days a week - is Sue Sadler.
"It's important to get all the families if we possibly can," she says. "So we spend a great deal of time chasing up the ones who are not good with questionnaires and appointments. This is time-consuming and very expensive."
Running Alspac has been costing Pounds 1 million per year. "Now, because we have started testing the children, it is Pounds 2 million," says Professor Golding. "We have something like 24 grants at any one time, with none lasting longer than three years." This is a hand- to-mouth existence for a unique project that she argues ought to be funded by a single agency. Now Professor Golding is cautiously optimistic that such a benefactor will be found.
Cot death offers an example of how the data will be used - and already is used. Evidence that babies laid to sleep on their backs were less likely to suffer sudden and unexplained death prompted the government to launch its Back to Sleep campaign. Professor Golding was able to use Alspac data to confirm the wisdom of this advice and also to find out if it has any adverse effects.
"The Americans in particular would not do a campaign because they were so convinced that putting children on their backs would be harmful. Our data persuaded them it would be safe."
Although the choice of information to collect was guided by a scientific steering committee with all sorts of testable hypotheses in mind, one of the glories of Alspac is that neither Professor Golding nor anyone else can predict what insights it will eventually offer.
Anyone with a theory may discover just the data required to confirm or refute it. The team may then find themselves grateful that they chose to measure that particular variable. Or it may be the other way round: the exact variable that somebody needs to know about turns out to be the one nobody thought to measure.
Still, you cannot expect to get it right all the time when the value of your epidemiology depends on second-guessing future needs that nobody knows they have.