Quality of life measurement tools for people with dementia and intellectual disabilities: A systematic review.

Only two studies were found across 10 databases, so the evidence base is extremely thin. The QUALID was validated only in Italian, so its performance in English-speaking intellectual disability services is unknown. The QUALID was designed for late-stage dementia where the person can no longer communicate, so it may not capture the experience of someone with mild intellectual disability and early dementia who can still talk about their own life. The DEMQOL-proxy study had only 9 participants and reported no reliability or validity data for this population. No self-report measures have been validated for adults with intellectual disabilities and dementia, so the person's own voice is missing from all available tools. The search was limited to English-language articles, potentially excluding relevant work in other languages. Both included studies used proxy or observational ratings rather than the person's own account, and proxy ratings are known to be influenced by the carer's own perceptions and mood.

No conflicts of interest declared by the authors.

Do not assume the QUALID is ready to use for your patients with intellectual disabilities and dementia. It was validated only in Italian and only for late-stage dementia where the person can no longer communicate. A person with mild intellectual disability and early dementia may still be able to talk about their own quality of life, and this tool would not capture that. The other tool, the DEMQOL-proxy, has no validation data for this group at all.