Gain in Alzheimer care INstrument--a new scale to measure caregiving gains in dementia.

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.