Methodological issues in the development of a national database for primary care groups and trusts

At the National Primary Care Research and Development Centre (NPCRDC) we ha ve constructed a national database for all primary care groups (PCGs) in En gland. At its core, the database links information about population socio-e conomic and demographic characteristics to generic health status and to the organisation, resourcing and activities of general practice. In this paper we describe and discuss the problems with linking these data, and with def ining the boundaries and the local populations of PCGs, given that they hav e been established on the basis of administrative expediency rather than ge ographical coherence. We then consider the implications of these difficulti es for needs assessment in primary care groups.