G N Giordano

The association between cannabis abuse and subsequent schizophrenia: a Swedish national co-relative control study.

Psychological Medicine January 2015 G N Giordano, H Ohlsson, Kristina Sundquist et al.

Although cannabis abuse (CA) is known to be associated with schizophrenia, the causal nature of this association is unclear, with prodromal effects complicating its interpretation. From Swedish national registry databases, we used a co-relative case-control design with full-sibling, half-sibling and first-cousin comparisons, alongside a general Swedish population sample. Using ICD codes, 5456...