If cannabis caused schizophrenia–how many cannabis users may need to be prevented in order to prevent one case of schizophrenia? England and Wales calculations.
Addiction, November 2009
—
BACKGROUND: We consider how many cannabis users may need to be prevented in order to prevent one case of schizophrenia or psychosis [defined as number needed to prevent (NNP)]. METHOD: Calculation for England and Wales using best available estimates of: incidence of schizophre…