TY - JOUR AU - Sitzia, J TI - How valid and reliable are patient satisfaction data? An analysis of 195 studies JO - Int J Qual Health Care VL - 11 PY - 1999 DO - 10.1093/intqhc/11.4.319 L3 - PubMed-ID: 10501602 SP - 319 EP - 328. ER -