Potential for Response Bias in Family Surveys About End-of-Life Care in the ICU

Abstract

After-death surveys are an important source of information about the quality of end-of-life care, but response rates generally are low. Our goal was to understand the potential for nonresponse bias in survey studies of family members after a patient's death in the hospital ICU by identifying differences in patient demographics and delivery of palliative care between patients whose families respond to a survey about end-of-life care and those whose families do not. We performed a cohort study of patients who died in the ICU at 14 hospitals. Surveys were mailed to family members 1 to 2 months after the patient's death. Chart abstraction was completed on all patients, assessing demographic characteristics and previously validated indicators of palliative care. Of the 2,016 surveys sent to families, 760 were returned, for a response rate of 38%. Patients whose family members returned the surveys were more likely to be white (88% vs 74%, respectively; p < 0.001); to be older (71 years vs 69 years, respectively; p = 0.015); and to have received more indicators of palliative care, including medical record documentation of family present at death, involvement of spiritual care, and dying after a decision to limit life-sustaining therapies (p < 0.05). Patients whose family members responded to a survey about end-of-life care were more likely to be white, older, and have indicators of palliative care documented in the medical record. Because these patients likely received higher quality palliative care, these findings suggest that the response bias in end-of-life care research is toward overestimating the quality of palliative care. ClinicalTrials.gov Identifier: NCT00685893.