Assessing quality of life in dementia: Preliminary psychometric testing of the Quality of Life Assessment Schedule (QOLAS)

Abstract

We adapted a generic, individualised, patient-centred quality of life (QOL) assessment technique, the Quality of Life Assessment Schedule (QOLAS) for use with patients with dementia. The QOLAS was administered to a group of patients with mild to moderate dementia alongside a number of other measures of well-being to assess its psychometric properties. Each patient's main carer also completed the QOLAS, giving a proxy rating of the QOL of the patient. The patients understood the interview and were able to describe their quality of life both qualitatively and quantitatively. In this preliminary study the QOLAS was demonstrated to have good validity (content, construct, and criterion) and good internal reliability. The carers rated the patients as having a worse QOL than did the patients themselves on all subdomains of the QOLAS. The results suggest that patients with mild to moderate dementia can rate their own QOL and that the QOLAS is a promising method for assessing QOL in this patient group. The discrepancy between the patients' own views and the views of their carers raises important issues about whether the patient or a proxy is the best judge of QOL in patients with dementia.

Health-related quality-of-life instruments for Alzheimer's disease and mixed dementia

“…Regarding validity, ten instruments showed good evidence of content validity Black et al, 1999;Brod et al, 1999;Logsdon et al, 1999;Selai et al, 2001a;Terada et al, 2002;Yamamoto-Mitani et al, 2002;Smith et al, 2005a;Trigg et al, 2007b). Despite the fact that criterion-related validity cannot be tested due to the lack of a gold standard, two measures Ready et al, 2002) claim to show some evidence of it, perhaps referring to convergent validity.…”

Measurement of health-related quality of life for people with dementia: development of a new instrument (DEMQOL) and an evaluation of current methodology

“…This lag is likely to be due to the methodological challenges in measuring patient-reported outcomes such as HRQoL in dementia. Between 1996 and 2002, seven new measures of HRQoL in dementia were developed, [83][84][85][86][87][88][89] in addition to an earlier measure. 90 These are reviewed below (section 'Critical review of measures of HRQoL in dementia', p. 9).…”

Quality of life of elderly with alzheimer’s disease: a comparative study between the patient’s and the caregiver’s report

“…These are: (1) QUALIDEM (4) , (2) Psychological Well-Being in Cognitively Impaired Persons (PWB-CIP) (5) , (3) DEMQOL (6) , (4) Quality of Life Assessment Scale on Alzheimer's Disease (QoL-AD) (7)(8) , (5) The Cornell-Brown Scale for Quality of Life in Dementia (CBS) (9) , (6) Dementia Care Mapping (DCM) (10) , (7) Quality of Life Assessment Schedule in Dementia (QOLAS) (11) , (8) The Quality of Life in Late-Stage Dementia Scale (QUALID) (12) , (9) Dementia Quality of Life Instrument (DQoL) (13) , (10) Activity and Affect Indicators of Quality of Life (14) .…”

“…The patient's report was considered in the DEMQOL (6) , QdV-DA (7)(8) , CBS (9) , QOLAS (11) and DQoL (13) only, which indicated adequate reliability and validity in assessment by patients with initial-stage dementia (7,9,11,13) . Although loss of discernment and conscience are common in dementia, some researchers believe this loss can be independent of the perception fo well-being and emotional states themselves (13) .…”