Validity, reliability, and feasibility of the German version of the Caregiver Reaction Assessment scale (G-CRA): a validation study

Background: Instruments measuring caregiver reactions usually disregard positive aspects, and focus predominately on home care. The Caregiver Reaction Assessment (CRA) scale is an exception. Until now, no German version has been available. We translated the instrument to German (G-CRA) and evaluated its psychometric properties and feasibility. Methods: Face-to-face interviews with 234 informal caregivers of persons with dementia were performed. Half of the persons with dementia (n = 118) had been recently admitted to institutional long-term care (iLTC); the remainder (n = 116) lived at home. Exploratory factor analysis (EFA) was performed. Subscales were inter-correlated and further correlated with the Zarit Burden Interview (ZBI), the General Health Questionnaire (GHQ-12), and the EuroQuol (EQ-5D). Internal consistency was measured (Cronbach's alpha), and interviewers (n = 9) appraised feasibility. The time needed to apply the scale was measured in 20 interviews. Results: The EFA yielded six factors (Kaiser criterion), but a scree plot supported the five dimensions of the original version that explained 56.2% of variance. Low-to-moderate subscales' inter-correlation was revealed. Highest correlation (r = 0.5) was found between impact on health and impact on daily schedule, indicating slight overlap. Criterion validity was supported by reasonable correlations between subscales and ZBI and GHQ-12 (r = -0.21-0.71). Subscale impact on health was negatively correlated with the EQ-5D. The internal consistency was sufficient (alpha = 0.67 - 0.78). Interviewers judged the G-CRA to be appropriate. Completion took 6.50 min (median value). Conclusions: Our results suggest that the G-CRA is sufficiently valid and internally reliable. The instrument is applicable in home care and iLTC as well as in the transitional phase.