Effects of Survey Mode, Patient Mix, and Nonresponse on CAHPS Hospital Survey Scores
Published In: HSR, Health Services Research, v. 44, no. 2, pt. 1, Apr. 2009, p. 501-518
Posted on RAND.org on December 31, 2008
OBJECTIVE: To evaluate the need for survey mode adjustments to hospital care evaluations by discharged inpatients and develop the appropriate adjustments. DATA SOURCE: A total of 7,555 respondents from a 2006 national random sample of 45 hospitals who completed the CAHPS Hospital (HCAHPS [Hospital Consumer Assessments of Healthcare Providers and Systems]) Survey. STUDY DESIGN/DATA COLLECTION/EXTRACTION METHODS: The authors estimated mode effects in linear models that predicted each HCAHPS outcome from hospital-fixed effects and patient-mix adjustors. PRINCIPAL FINDINGS: Patients randomized to the telephone and active interactive voice response (IVR) modes provided more positive evaluations than patients randomized to mail and mixed (mail with telephone follow-up) modes, with some effects equivalent to more than 30 percentile points in hospital rankings. Mode effects are consistent across hospitals and are generally larger than total patient-mix effects. Patient-mix adjustment accounts for any nonresponse bias that could have been addressed through weighting. CONCLUSIONS: Valid comparisons of hospital performance require that reported hospital scores be adjusted for survey mode and patient mix.