Table 1 - The control group had higher levels of school (p<0.05) and post school (p<0.01) education than the schizophrenia and methamphetamine-induced psychosis groups; the methamphetamine-induced psychosis group had earlier onset of methamphetamine use compared to the schizophrenia group (p<0.05), longer duration of methamphetamine use (p<0.0001) and shorter duration of abstinence from methamphetamine (p<0.05) than the schizophrenia and control groups; the schizophrenia and methamphetamine-induced psychosis groups scored higher than the control group on the PANSS positive scale score (p<0.0001), PANSS negative scale score (p<0.0001), PANSS general psychopathology scale score (p<0.0001); PANSS total score (p<0.0001) and CGI-S score (p<0.0001); the control group scored higher than the methamphetamine-induced psychosis and schizophrenia groups on the GAF (p<0.0001); the methamphetamine-induced psychosis group scored higher than the schizophrenia and control groups on the KMSK Cocaine lifetime total score (p<0.05), Heroin lifetime total score (p<0.001), Cannabis lifetime total score (p<0.01), KMSK Methamphetamine total score (p<0.0001).