Measuring Shared Decision-Making from People with Dementia (PwD) Perspective: An Adaptation and Validation Study on Shared Decision-Making Questionnaire about Pwd Care Arrangement

Background and Purpose:

Care arrangement decisions between people with dementia (PwD) and their adult child caregivers significantly impact the entire family, shaping the care environment and influencing subsequent decision-making. Although person-centered care principles acknowledge that PwD retain decision-making capacity, either independently or with caregiver support, their perspectives are often overlooked in decision-making process. Furthermore, research on shared decision-making (SDM) predominantly relies on caregiver reports, neglecting PwD’s voices. To address this gap, this study aims to translate, adapt, and validate the Shared Decision-Making Questionnaire (SDM-Q-9) from PwD’s perspective in the context of Chinese care arrangements.

Methods:

A total of 122 community-dwelling older adults with dementia (measured by Montreal Cognitive Assessment, MoCA) completed the Shared Decision-Making Questionnaire (SDM-Q-9), alongside the Modified version of Control Preferences Scale (CPS _post), and Decision Regret Scale (DRS) from August 2024 to January 2025 at the clinics in Shanghai, China. Average inter-item correlation (AIIC) and item-total correlation (ITC) were used to select items. Psychometric validation included internal consistency (Cronbach’s α), principal components analysis (PCA) with varimax rotation, and confirmatory factor analysis (CFA) to test structural validity. Construct validity was assessed through the correlations between SDM-Q-9, CPS _post, and DRS.

Results:

Participants’ mean age was 73.918 years (SD=6.497), with 68.852% women. MoCA yielded a median score of 14 (interquartile range: 11-19) under the adjusted by education year (1-point correction for education ≤ 12 years). Four items with low average inter-item correlation (AIIC<0.3) and moderate item-total correlation (ITC=0.484–0.556) were removed, resulting in a shortened SDM-Q-5 that strongly correlated with the original SDM-Q-9 (r= 0.919, p<0.01). The SDM-Q-5 demonstrated good internal consistency (α= 0.758>0.70) and a unidimensional structure (51.550% variance explained), with factor loadings ranging from 0.589 to 0.778. Kaiser-Meyer-Olkin confirmed sampling adequacy (KMO=0.750, p<0.001). CFA supported good model fit (χ²= 8.887, df= 5, p>0.05; CFI= 0.985, TLI= 0.980; RMSEA= 0.080, SRMR= 0.070). The scale showed weak convergent validity with actual role experienced (CPS _post: r= 0.190<0.3, p< 0.05) but initially supporting good discriminant validity with decision regret (DRS: r= -0.026, p> 0.05).

Conclusions and Implications:

This study was the first to directly measure shared decision-making from the perspective of PwD regarding care arrangements instead of reliance on proxy reports. The Chinese version SDM-Q-5 had good internal consistency, structural validity, and discriminant validity. Future studies should validate the scale in larger, more diverse populations and explore cross-cultural adaptations to enhance generalizability. These findings emphasized the importance of incorporating PwD’s voices in care decisions, aligning with person-centered care principles.