This is, like, the fifth time I’ve seen this headline. Everytime the mention that one study that says people get the disorder from eating too much cat shit. Sure. That totally sounds like a thing that happens often enough for a study to find that as a significant cause. This article, however, said that study met “mixed reception.” So it went on for a few minutes without saying anything and concluded “We just don’t know enough about the link between schizophrenia and cats.” This, my comrades, is real science.
Well if you do some kind of fucked up intervention you could prove a direct causal link, but I doubt it would be sufficient to rule out emergent symptoms. The subjects would likely react differently to laboratory conditions (perhaps weakening the immune system?). So you would only be testing a narrow hypothesis of how the parasite effects the subject. You would also neglect to find a baseline of how much contamination you could expect in the dwelling. So you could have a diet soda situation if you had 100x more exposure than is reasonable there is a risk but its not relevant
I believe a larger longitudinal non-intervening observation is both ethical and useful for establishing context.