A 3-Item Screening Scale for Caregiver Burden in Dementia Caregiving: Scale Development and Score Mapping to the 22-Item Zarit Burden Interview

Abstract

Objectives: Brief screening scales for caregiver burden are much needed in routine dementia services to efficiently identify caregivers of persons with dementia (PWD) for further intervention. Although the 22item Zarit Burden Interview (ZBI) is often used, its available screening versions have not performed as well as the full version in distinguishing significant burden. We developed a brief screening scale that is valid and comparable to ZBI in distinguishing caregiver burden. Design and setting: Baseline data of an ongoing cohort study. Participants: Family careivers of community-dwelling PWD (n ¼ 394). Measures: Participants completed questionnaires containing ZBI and other caregiving scales. Initially, we split the study samples into 2dthe derivation sample (n ¼ 215) was used to develop a brief scale that best distinguishes significant burden (using the best-subset approach with 10-fold cross-validation), whereas the validation sample (n ¼ 179) verified its actual performance in distinguishing significant burden. We then evaluated the derived scale in its internal consistency reliability, factorial validity, known group validity, and construct validity, and mapped the scores between the brief scale and ZBI using the equipercentile equating method. Results: We derived a 3-item scale which had comparable performance to ZBI in distinguishing significant burden (area under the receiver operating characteristic curve 0.86, 95% confidence interval 0.81-0.92). It had a single dimension in exploratory factor analysis and maintained good psychometric properties similar to those of ZBI. It also explained 77.8% of the variability in ZBI, and had scores that could be mapped to ZBI with reasonable precision. Conclusions and Implications: We have derived a highly accessible tool to screen for caregiver burden, which can have a wider health system effect of expanding the reach of caregiver-focused interventions to services involved in the care of PWD. Notably, this screening tool was developed using rigorous methods and demonstrated comparability to ZBI in its validity, reliability, and total scores.

Exploratory factor analysis of the caregiver grief inventory in a large UK sample of dementia carers

“…By having a brief grief scale such as the MM-CGI-SF readily available in routine practice, practitioners can identify caregivers with high AG who may benefit from further grief focused, psychological interventions. Caregivers with high AG may also be missed by other commonly used scales, such as the Caregiver Burden Scale (Liew & Yap, 2019) and the Caregiver Strain Index (Sullivan, 2002). Such interventions may help caregivers cope with multiple, incremental losses associated with the pre-death grieving process, as well as the coinciding complex emotions involvedwhich are recognised in the MM-CGI-SF scale.…”

The hidden patient

“…[ 15 ] Caregiver burden can also be measured using validated scales, such as the Zarit caregiver burden scale. [ 16 17 ] There is always opportunity to talk to caregivers about their mood, or to discuss various activities of daily living (ADLs) or instrumental ADLs for the patient that are not being met. Providers may also involve social work colleagues to further explore caregiver well-being and support needs.…”

Active case finding of dementia in ambulatory care settings: a comparison of three strategies

“…In general, AUC > 0.9 is deemed to be excellent performance [50] and indicates that a strategy has a low error rate (<10%) and is suitable for case-finding purposes. AUC was also compared among the three strategies via a non-parametric approach proposed by DeLong et al [20,21,31,[51][52][53] with statistically significant differences defined as P ≤ 0.05 and clinically significant differences defined as AUC differences of ≥1% (when a test is used for case finding in a large population of one million people, a 1% difference in AUC would have translated into an additional 10 000 people being misclassified) [21].…”