I have a friend who works at a university research department and he told me that one of the biggest problems he had realised is that the majority of studies into everything are typically based upon students. He told me that the reason is quite simple, the majority of studies payout tiny amounts of money, to students that money is worthwhile but to adults it's not. So, the majority of studies involve students looking to get paid tiny amounts of money which those in working society would never consider doing.
He told me that was why the vast majority of studies – especially around sex – are a total and utter waste of time as the information that they put out is simply not worth the paper it's printed on simply due to not having used a wide enough demographic to garner the information.
On a side note, he also told me that the vast majority of studies are used on the Internet to say things completely different to what they actually show. This is something I've seen many times ever since he pointed out, it's scary how many people misuse information. I think one of the most misused studies is the one from Tinder, which said that the top 80 percent of women only match with the top 20 percent of men. The amount times I see this used as a way to argue that women are too picky, when in fact what it actually shows is that the vast majority of dating app users are men, is crazy.
So, the problem is not just that large numbers of the studies are not representing accurate information due to not using a wide enough demographic pool, too many studies are simply being used to sell ideas and messages that the studies don't actually even show.
Well done for pointing this out, I don't know what the solution is but it is important more people realise that a lot of data from studies – especially sex-based ones – are not representative of reality!