Doll therapy in residential dementia care in China: protocol for an exploratory pilot and feasibility mixed-methods cluster randomized controlled trial

Background: Behavioral and psychological symptoms of dementia commonly drive psychotropic prescribing in residential care. Doll therapy is a person-centered, attachment-informed intervention that may reduce distress and support engagement, but evidence from Chinese nursing homes remains limited. This protocol describes an exploratory pilot and feasibility mixed-methods cluster randomized controlled trial of a staff-mediated doll-therapy care package plus routine nursing care versus routine nursing care alone. Methods and analysis: Phase I is a pragmatic, parallel-group, 1:1 cluster randomized pilot trial in six nursing homes in Zhengzhou, China, targeting 142 residents with dementia. Intervention homes will receive a structured doll-therapy introduction of eight planned sessions over approximately 15 days, continued access to a personal doll during routine care, staff training, structured interaction, relational engagement, and routine-care implementation; control homes will provide routine nursing care alone. Assessments occur at baseline, 6 weeks, and 12 weeks. The registered primary outcome is class-specific mean daily medication dose over 12 weeks for antipsychotics, anxiolytics, and antidepressants, interpreted as an indirect medication-stewardship signal. The main proximal clinical outcome is total Neuropsychiatric Inventory-12 score. Secondary and contextual outcomes include Barthel Index, cognitive enhancer use, traditional Chinese medicine use, and structured engagement with the doll. Phase II uses semi-structured interviews with staff and family caregivers from intervention homes to examine acceptability, implementation, training needs, cultural fit, and ethical considerations. Quantitative analyses will emphasize effect estimates, confidence intervals, cluster-level summaries, and randomization/permutation-based robustness checks; qualitative data will be analyzed thematically. Discussion: The study will provide feasibility, acceptability, fidelity, safety, preliminary clinical-signal, and implementation evidence to inform a future adequately powered cluster trial in Chinese residential dementia care. Trial registration: https://clinicaltrials.gov/study/NCT06506487, ClinicalTrials.gov, NCT06506487. Registered July 16, 2024.