Objective: To describe and validate a new scale, Gain in Alzheimer care Instrument (GAIN), and to measure gains in dementia caregiving.
Design: Items in GAIN were derived through a qualitative study of family carers of persons with dementia (PWD). Content validity of GAIN was established by a team of dementia care experts (geriatrician, nurse, and social worker) and through focus group discussion with 15 family carers. Consecutive carers of PWD were administered a questionnaire containing GAIN and other measures.
Setting: Ambulatory dementia clinic of a tertiary hospital and the local Alzheimer's Association.
Participants: Family carers of PWD.
Measurements: The psychometric properties of GAIN were examined, in particular, exploratory factor analysis and construct validity through correlation with extant measures; Positive Aspects of Caregiving (PAC), Dementia Management Strategies Scale (DMSS), and Zarit Burden Interview (ZBI).
Results: Two hundred thirty-eight English-speaking carers completed the survey. Mean age of carers was 50.1 year (standard deviation [SD] 10.1) and females (68.1%) and child carers (81.3%) comprised the majority. Mean GAIN score was 30.5 (SD 6.5). Internal consistency of GAIN by Cronbach's alpha was 0.89 and test-retest reliability (2 weeks) by Intraclass Correlation Coefficient was 0.70. GAIN correlated strongly with PAC (r = 0.68, df = 236, p <0.0001), moderately with DMSS (encouragement) (r = 0.35, df = 234, p <0.0001) and DMSS (active management) (r = 0.42, df = 235, p <0.0001), and modestly with DMSS (criticism) (r = -0.14, df = 236, p = 0.03) and ZBI (r = -0.15, df = 236, p = 0.02). Principal component analysis revealed a single component with an Eigen value >1 at 5.28, accounting for 52.8% of the variance.
Conclusion: GAIN is a psychometrically reliable and valid instrument for measuring gains in dementia caregiving. It adds an important dimension to carer assessment in dementia.