Generating social class data in primary care.

The objective of this study was to compare three methods of collecting social class data in general practice. The setting was a rural dispensing practice on the Nottinghamshire/Lincolnshire border. The methods examined were: (a) a self-administered questionnaire to 200 patients to determine their social class based on the occupation of the head of household; (b) members of the practice staff were asked to assign a social class to these households based on their local knowledge; and (c) use of small area statistics from the 1991 census data using modal and weighted methods. It was found that the practice staff were unable reliably to assign a social class to the households. The modal method of using small area statistics to assign social class to households through their postcode and its link to the census data was also inaccurate. While a personal questionnaire will remain the only method for assigning a social class to individual patients for clinical care or most research, the weighted method of small area statistics is shown to be a cost-effective and sufficiently accurate method for health needs assessment in general practice.