What dimensions underlie patient responses to the general practice assessment survey? A factor analytic study

Abstract

Background. Patient self-report measures of primary care are being used increasingly for quality assessment and improvement. The General Practice Assessment Survey (GPAS) is a widely used measure. However, it is important that the measures used are valid and interpretable. Factor analysis is a useful method to assist in validation. Objective. The aim of this study was to determine the underlying structure of responses to the GPAS. Methods. Factor analysis of data from a number of patient surveys was carried out using the GPAS in primary care. Results. Analysis indicated that three factors underlie responses to the GPAS. These were named 'access', 'patient-centredness' and 'nursing'. These factors were replicated in a second sample of GPAS survey data. Conclusion. Responses to the GPAS can best be summarized in terms of three underlying factors, which supports previous conceptual work. These factors may also have utility for reducing the overall length of the GPAS, and in reducing the need for multiple hypothesis testing associated with the use of the original scales.