What’s the real difference (evidence) between Religion and Schizophrenia?

This is something of a problematic question, and my first take on it is that it was asked contemptuously, or in bad faith. It's also very easy to infer you imagine schizophrenia as Hollywood insanity, what is used to justify Mrs. Voorhees or Michael Meyers as slasher killers rather than as an actual mental health diagnosis from the DSM. I can't help but wonder if you regard all persons who suffer from mental illness as violent or degenerate or otherwise less of a person than those who are undiagnosed.

So one difference between religion and schizophrenia is this: The psychiatric sector estimates one in three-hundred people worldwide content with schizo-effective disorders. 251 people in three-hundred are associated with an organized religion. As identities and clubs go, religions are way popular.

In fact, there are multiple fields of study about the interaction between religious practice and mental health, including abnormal psychology, or the study of mental illness, so I'm not going to imagine I can infer the meat of your juxtaposition.

Diagnoses are not intended for any other use than to inform treatment for the patient. They are especially not used to deny civil rights to a given person because they received a diagnosis from a medical professional. In order for someone to be committed (in a modern, civilized society) they have to be an imminent danger to themselves or others, which has to be established beyond a diagnosis.

Schizophrenics are statistically less of a danger to themselves or others than the general population. They are represented disproportionately among victims of violence, including officer-involved violence. And schizophrenics can sometimes operate heavy machinery, including firearms, safely and expertly. That doesn't mean they aren't affected by their illness, just that in some cases, it doesn't interfere with their career. Contrast religious people who, as a demographic, are more violent than the general population and are convicted of violent crime more often than the general population, but not by much, since most of the general population is religious.

Irreligious people, like tabletop role-players are just not very violent.

All that said, I don't know what exactly you were trying to ask. I read it something like what's the difference between an orange and a sparrow egg? Well, one's bigger?