This is almost certainly survivorship bias[1]. Only middle-height cats that might theoretically survive are going to be taken to a veterinarian; the cats that fell from higher heights were not included, because they were "obviously dead". Which makes "high-rise syndrome" an example of the exact type of bias discussed in this paper.
> Strangely, cats that fall from a height under 6 stories have more severe trauma than those that fall from over 6 stories.
So, the theory is, if a cat falls from a height above 6 stories they either have less severe injuries or are just dead so the owner just doesn't bring them to the vet?
>>6 stories they either have less severe injuries or are just dead so the owner just doesn't bring them to the vet
I would guess that at that height something must've broken the fall such that the cat suffered almost no injuries. I really don't see how the cat would survive the fall otherwise.
Cats are much smaller than humans and better prepared to absorb impact after "floating" to ground. I assume breaking the fall would actually be dangerous to cats because it disturbs their approach.
[1] https://en.wikipedia.org/wiki/Survivorship_bias#In_cats