Objective-To develop general practice profiles of needs and demand for primary health care. Design-Postal survey of a stratified random sample of 3478 people registered with five general practices. Data from a single practice were compared with data from the remaining four to identify areas of comparative need. Setting-Five general practices in Lothian. Main outcome measures-Differences between the single practice and the comparison practices in terms of social and economic circumstances, limiting long term illness, specific ongoing conditions, minor illness or symptoms, psychosocial problems, discussion of lifestyle, associated use of services. Results-Respondents from the single practice reported higher rates than those in the four comparison practices of ongoing mental health and respiratory problems and use of antidepressants, tranquillisers, or sleeping tablets. Although rates of limiting long term illness and other specific ongoing conditions were comparable, the rates of minor illness or symptoms and psychosocial difficulties were higher in the single practice. Respondents from the single practice were more likely to consult frequently, to have contacted the practice out of normal working hours, and to have discussed psychosocial difficulties with a general practitioner. For any specific ongoing condition or ''minor'' illness, respondents from the single practice were no more likely to consult. Conclusions-A comparative survey approach is a useful method of developing an understanding of patterns of need and demand among general practice populations. It has the potential to inform planning within individual general practices and the process of commissioning among general practices within a given area.
