A psychologist discovers that the blood of patients with schizophrenia contains a certain chemical not found in the general population. This means that

Question

Quizplus · Accepted Answer

The discovery only establishes a correlation between the chemical and schizophrenia, not a causal relationship. It's possible that the chemical is a byproduct of schizophrenia, that schizophrenia causes the production of the chemical, that both are caused by another factor, or that their relationship is coincidental or indirect.

A Psychologist Discovers That the Blood of Patients with Schizophrenia