In a large-scale Taiwanese study, 445 MA users from a psychiatric hospital and criminal detention were assessed to determine the relationship of pre-morbid personality traits, social function, and other psychiatric disorders to MA-induced psychosis (Chen et al., 2003). Thirty-nine percent met criteria for lifetime history of MA-induced psychosis. Early initiations of MA use, use of larger amounts of MA, and higher scores on measures of pre-morbid schizoid/schizotypal personality traits were all associated with increased risk of psychosis.
