PT - JOURNAL ARTICLE AU - Peter Bower AU - Martin O Roland TI - Bias in patient assessments of general practice: general practice assessment survey scores in surgery and postal responders. DP - 2003 Feb 01 TA - British Journal of General Practice PG - 126--128 VI - 53 IP - 487 4099 - http://bjgp.org/content/53/487/126.short 4100 - http://bjgp.org/content/53/487/126.full SO - Br J Gen Pract2003 Feb 01; 53 AB - Patient-based measures of the quality of primary care are increasingly important. However, their effective use requires bias to be minimised. Scores on the General Practice Assessment Survey (GPAS) differ according to whether patients are surveyed in the surgery or by post. It is not clear whether these differences relate to the mode of administration or to the types of patients who complete the scale in postal and surgery samples. Regression indicates that the bias reflects both effects and should be considered when GPAS scores are being interpreted.