Follow up studies: a case for a standard minimum data set.

A vast amount of information is collected on the subsequent health and development of babies who are born early or small, as well as about babies who are ill around the time of birth, or who have had a particular treatment or intervention. This information is collected for diVerent reasons and in several diVerent ways. Some data are collected as part of prospectively planned follow up studies, and some in hospital based, follow up, and specialist clinics. Data are also collected routinely by people providing care in the community, including community paediatricians, general practitioners, and health visitors. Although such information is of great potential interest to parents, to providers of obstetric and neonatal care, to those responsible for purchasing care and to the public at large, much of it is inaccessible and never used. This is because there is no central focus for collecting together data on childhood morbidity; the diversity of purposes means there is little agreement on which data should be collected and definitions are not standardised There are also wide local diVerences in the ways in which data are collated, tabulated, and reported. Broadly, there are two reasons for following up children. First, an assessment can be done as a continuing service for the children and their families after an acute illness, and this focuses on the health and development of the individual child. This is done to identify the child’s health and other needs, and provide reassurance, advice, and information for parents. The information from the assessment can be fed back to nursing and medical staV who treated the baby, albeit at an anecdotal local level. This type of follow up may be hospital or community based. The information obtained can also form part of a continuing record of the child’s status—for example, on the district based computerised child health systems. The second reason for follow up is to obtain a more systematic overview of the long term eVect of events at or around birth on particular groups of babies. These can be, for example, those who have needed neonatal intensive care, or those within a particular birthweight group, or those who have had an intervention within the context of a controlled trial. The underlying questions are to do with evaluation of care, cost eVectiveness issues, the impact of changing mortality rates on morbidity, or monitoring diVerences in rates of morbidity over time or between areas. Here the outcomes sought may be very detailed and targeted to specific areas of function. Follow up of this type is usually funded as a research project and some of the observations and findings are to be found in medical publications. All this activity undoubtedly addresses many research issues related to specific interventions or categories of care, and provides a good continuing service for individual children, but other questions remain unanswered. For example, it is diYcult at present to answer questions about trends over time on the rate of disability in extremely preterm babies, or the numbers of low birthweight survivors who may need additional health and educational services in later childhood. This is because the numbers of children included in any one study or report are usually small, and fluctuations over time in the number of children with an adverse outcome cannot be distinguished from random variations. The way to overcome this is to pool study findings, but this is diYcult because in study reports, groups of babies are defined in diVerent ways, the children are seen at different ages, and their outcomes described in a variety of ways. So how can we tap this vast pool of unused information? One way forward might be to collect an agreed simple common core of data on each child seen at follow up, for whatever reason. This would describe his/her health and development at a specific age and be collated at district level. When appropriate, it could be available in published reports. Two years ago, the first steps were taken towards this goal. Two national working groups agreed a standard core of data to describe the health and functional status of children at the age of 2 years. This focused on describing the level of function of the child within a number of domains, clearly defining those with a severe level of functional loss. The underlying impairment or disease was stated secondarily. Three identifiers were also suggested: the NHS number of the mother and of the child, and the date of birth of the child. These would facilitate linking with other data sets, particularly if the NHS number of the baby were allocated as soon as possible after birth. In view of the Archives of Disease in Childhood 1997;76:F61–F63 F61