The validity and reliability of scales for the evaluation of end-of-life care in advanced dementia

The lack of valid and reliable instruments designed to measure the experiences of older persons with advanced dementia and those of their health care proxies has limited palliative care research for this condition. This study evaluated the reliability and validity of 3 End-of-Life in Dementia (EOLD) scales that measure the following outcomes: (1) satisfaction with the terminal care (SWC-EOLD), (2) symptom management (SM-EOLD), and (3) comfort during the last 7 days of life (CAD-EOLD). Data were derived from interviews with the health care proxies (SWC-EOLD) and primary care nurses (SM-EOLD, CAD-EOLD) for 189 nursing home residents with advanced dementia living in 15 Boston-area facilities. The scales demonstrated satisfactory to good reliability: SM-EOLD (alpha = 0.68), SWC-EOLD (alpha = 0.83), and CAD-EOLD (alpha = 0.82). The convergent validity of these scales, as measured against other established instruments assessing similar constructs, was good (correlation coefficients ranged from 0.50 to 0.81). The results of this study demonstrate that the 3 EOLD scales demonstrate "internal consistency" reliability and demonstrate convergent validity, and further establish their utility in palliative care dementia research.