Detecting pre-death grief in family caregivers of persons with dementia: measurement equivalence of the Mandarin-Chinese version of Marwit-Meuser caregiver grief inventory

BACKGROUND: Pre-death grief (PDG) is a key challenge faced by caregivers of persons with dementia (PWD). Marwit-Meuser Caregiver Grief Inventory (MM-CGI) and its abbreviated MM-CGI-Short-Form (MM-CGI-SF) are among the few empirically-developed scales that detect PDG. However, they have not had a Mandarin-Chinese version even though Chinese-speaking populations have among the largest number of PWD. We produced a Mandarin-Chinese version of MM-CGI and evaluated whether it had equivalent scores and similar psychometric properties to the English version. METHODS: We produced the Chinese MM-CGI through the methods of forward-backward translation and cognitive debriefing. Then, we recruited family caregivers of PWD (n = 394) to complete either the Chinese (n = 103) or English (n = 291) version. The two versions were compared in their score-difference (adjusting for potential confounders using multiple linear regression), internal-consistency reliability (using Cronbach’s α) and test-retest reliability (using intraclass correlation-coefficient), known-group validity (based on the relationship with the PWD and stage of dementia) and construct validity (using Spearman’s correlation-coefficient). RESULTS: The two versions showed similar mean scores, with the adjusted score-difference of 1.2 (90% CI -5.6 to 7.9) for MM-CGI and − 0.4 (90% CI -2.9 to 2.1) for MM-CGI-SF. The 90% CI for adjusted score-difference fell within predefined equivalence-margin (±8 for MM-CGI and ± 3 for MM-CGI-SF) and indicated equivalence of the scores. The two versions also demonstrated similar characteristics in reliability and validity. CONCLUSIONS: The Chinese MM-CGI opens the way for PDG assessment and intervention among Chinese-speaking caregivers. Establishing its measurement equivalence with the English version paves the way for cross-cultural research on PDG in dementia caregiving. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12877-018-0804-5) contains supplementary material, which is available to authorized users.