The data was collected during structured interviews of 80 participants meeting DSM criteria for schizophrenia or schizoaffective disorder. This occurred over a 17 month period from November 2011 to April 2013. Details are available in the thesis titled 'efficacy of garcinia mangostana L. (Mangosteen) pericarp as an adjunctive to second generation antipsycjotics for the treatment of schizophrenia: A double blind, placebo controlled trial'.