Reliability and validity of the Dementia Quality of Life measure in nursing home residents.

The purpose of this study was to test the reliability and validity of the Dementia Quality of Life (DQOL) in a sample of 486 residents from 12 nursing homes in the greater Baltimore area. There was some evidence of validity of the DQOL based on confirmatory factor analysis and Rasch model testing and criterion-related validity. Reliability of the DQOL was somewhat supported in this study based on internal consistency and test-retest reliability. Alpha coefficients and R(2) estimations were generally low across all of the subscales. Despite these findings, the subscale scores remained consistent over a 12-month period. The use of the single-item question about QOL may not be an accurate reflection of QOL among nursing home residents. These findings provide additional information about the psychometric properties of the DQOL and offer some recommendations for revisions in the measure to optimally measure QOL in nursing home residents.