Effects of survey mode on results of a patient satisfaction survey at the observation unit of an acute care hospital in Singapore.

INTRODUCTION Over the years, surveys have become powerful tools for assessing a wide range of outcomes among patients. Healthcare managers and professionals now consider patient satisfaction as an outcome by itself. This study aims to determine if results of a patient satisfaction survey are affected by the manner by which the survey instrument is administered. MATERIALS AND METHODS A patient satisfaction survey was conducted from May 2006 to October 2007 in a tertiary level acute care facility. All patients admitted to the observation unit during the study period were invited to participate. Using a contextualized version of the Consumer Assessment of Healthcare Providers and Systems (CAHPS) Hospital Survey, data was collected through either a phone interview, face to face interview or self-administered questionnaire. Each of these survey modes was administered during 3 different phases within the study period. RESULTS Eight hundred thirty-two (832) patients were included in the survey. Based on results of univariate analysis, out of the 18 questions, responses to 11 (61.1%) were related to survey mode. Face-to-face interview resulted in the greatest proportion of socially desirable responses (72.7%), while phone interview yielded the highest proportion of socially undesirable responses (63.3%). After controlling for possible confounders, logistic regression results showed that responses to 55.6% of the questions were affected by survey mode. Variations in response between phone interview and self-administered questionnaire accounted for 87.5% of the observed differences. CONCLUSIONS Researchers must be aware that the choice of survey method has serious implications on results of patient satisfaction surveys.