"People with dementia don't remember things"

My mother, who has dementia, was on a psycho-geriatric ward for assessment for a month in the summer.

She has now been sent a survey asking about her "recent experiences as an inpatient". Of course she doesn't even remember being in the hospital, let alone whether she saw any leaflets telling her how to complain and all the other stuff she is being asked.

The letter with the survey says that if she doesn't respond they will write and remind her. I think this means that I, as her carer, has to deal with this along with all the other things I have to do for her as well as doing my job and everything else. I feel I could do without it.

Is it possible for whoever selects the sample work not to include people who were on this ward as many are unlikely to be able to give rational responses to questionnaires, and sending them just means extra work for carers?