Aim Ensuring older adults' involvement in their care is accepted as good practice and is vital, particularly for people with dementia, whose care and treatment needs change considerably over the course of the illness. However, involving family members in decision making on people's behalf is still practically difficult for staff and family. The aim of this review was to identify and appraise the existing quantitative evidence about family involvement in decision making for people with dementia living in residential aged care.

Methods: The present Joanna Briggs Institute (JBI) metasynthesis assessed studies that investigated involvement of family members in decision making for people with dementia in residential aged care settings. While quantitative and qualitative studies were included in the review, this paper presents the quantitative findings. A comprehensive search of 15 electronic databases was performed. The search was limited to papers published in English, from 1990 to 2013. Twenty-six studies were identified as being relevant; 10 were quantitative, with 1 mixed method study. Two independent reviewers assessed the studies for methodological validity and extracted the data using the JBI Meta Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI). The findings were synthesized and presented in narrative form.

Results: The findings related to decisions encountered and made by family surrogates, variables associated with decisions, surrogates' perceptions of, and preferences for, their roles, as well as outcomes for people with dementia and their families.

Conclusions: The results identified patterns within, and variables associated with, surrogate decision making, all of which highlight the complexity and variation regarding family involvement. Attention needs to be paid to supporting family members in decision making in collaboration with staff.