To assess the performance of general practices, it is better to ask patients about their actual experiences of care rather than ask for satisfaction ratings, according to new research from the University of Bristol published in the British Medical Journal on 15 October. The findings call into question the reliability of using surveys to evaluate practice performance.

Patient surveys are used to assess the performance of doctors and  practices, and they increasingly enquire about specific patient experiences (for example, waiting time for an appointment) as well as overall satisfaction.

In the UK, general practices receive some of their income according to survey scores.  It is therefore important to be sure that patients' responses act as a reliable indicator of performance, yet few studies have looked into this.

Professor Chris Salisbury and colleagues from the University of Bristol set out to explore whether responses to survey questions reflect differences between the practices, the doctors, or the patients themselves.

Using mathematical models, they analysed data from 4,573 patients who consulted 150 different doctors at 27 general practices in England.  They found that specific questions about patients' experiences (particularly access to care) are a more accurate measure of practice and doctor performance than are questions about patients' general satisfaction.

This is largely due to differences in people's perceptions as well as random error, and suggests that the reliability of using surveys to assess an individual doctor's performance is questionable, say the authors.

They also found that responses vary according to patient characteristics such as age, sex, and ethnicity.  However, adjusting for these characteristics made very little difference to practices' scores or the ranking of individual practices.

In conclusion, they support the concept that questions about specific  experiences of care provide a more discriminating measure of a practice's performance than do subjective questions about general satisfaction.  And they call for their findings to be replicated in a larger sample of practices.

An accompanying editorial argues that measures of patient satisfaction need to be refined, but they are not hopelessly flawed.

Chris Salisbury, Marc Wallace, Alan A Montgomery.  Patients’ experience and satisfaction in primary care: secondary analysis using multilevel modelling. BMJ 2010; 341: c5004 doi:10.1136/bmj.c5004