Use of Read codes in development of a standard data set.

General practice has a wealth of data that could be used for purposes such as assessing health needs, planning, and audit. If this potential is to be realised appropriate data must be easily accessible and of high quality. This article describes the experience of an information project team in developing and coding a standard data set, with the aim of meeting the needs of commissioners, public health, and general practitioners. The Read coding classification seemed the logical choice for the standard data set because Read codes are the basis of a standard classification of general practice data. However, the coding structure has several weaknesses that were difficult to resolve, and the standard data set had to be changed to match available codes. This paper may prove helpful to similar project teams attempting to develop and use a standard data set.