"... many people believe that marijuana causes mental illness, in particular, schizophrenia. Several correlational studies have shown that heavy marijuana users are more likely to be subsequently be [sic] diagnosed with schizophrenia... However, there is no way for correlational studies to rule out the possibility that the correlation between heavy marijuana use and schizophrenia occurs because people who are predisposed to develop schizophrenia also tend to use marijuana."
"... many people believe that marijuana causes mental illness, in particular, schizophrenia. Several correlational studies have shown that heavy marijuana users are more likely to be subsequently be [sic] diagnosed with schizophrenia... However, there is no way for correlational studies to rule out the possibility that the correlation between heavy marijuana use and schizophrenia occurs because people who are predisposed to develop schizophrenia also tend to use marijuana."