"Are you able to read and understand the information we give you?"
Oh look, that works too.
Would that be seen as less rude and intrusive? Would it get the same information as asking education level?
If when I had my first, I had been asked if I could read and understand the information, I would have said yes. Absolutely. I remember when I was very slowly asked if I knew what immunizations were for thinking 'I'm an immigrant, not an idiot doctor' and snapped 'of course'. I, and my child, could have used someone who wasn't patronizing, but still spoke about the risks in a way I could understand as I was overwhelmed by a lot of scaremongering that was going on at the time even if I didn't want to admit it. I wasn't less intelligent, I was a 19 year old with little experience of reading medical jargon and little experienced support that wasn't riling me up with scare stories (being told my sister got very ill when she had that jab but no further details was awful for my mental health, my mother loved to do shit like that).
If I had been asked my education level at the time, I'd have said I finished high school with a few college classes.
If I'd been asked if I had GCSEs or A-levels, I would have said no, because I didn't immigrate until I was 17, but that I did finish high school in the US.
Those all give a different picture. It is important to look into how these things are asked, part of looking at this data is seeing which areas are marginalized groups struggling in more so and which they're not to explore best and harmful practices. Sometimes these questions are asked in a terrible way, the list off of questions eases some but can rile others. It's an area that needs work.
I'm reminded of years back when there was a study in breastfeeding in a working class area that involved vouchers and regular medical visits to see if that would improve rates, and so many were quick to call that offensive and rude to do that kind of research (and were really insulting to the mothers involved with a lot of 'I handexpressed into tubes to feed mine while working with no help and if they can't do it, then they must not really care about breastfeeding' and 'they're just in it for the money'). There is a lot going on to improve things, but it's difficult with how research works and how whenever there are attempts that get any media attention, people are quick to judge both the researchers involved and the parents who take part. Some just want to assume the worst, some are just more sensitive on certain topics so these stand out more, and some just like riling people up.