4. To date there are three published placebo controlled trials of OT in SCZ. In the first study, OT was given in a placebo-controlled double-blind randomized crossover design (Feifel et al. 2010). In this study of fifteen completers, the Positive and Negative Symptom Scale (PANSS) and the Clinical Global Impressions scale (CGI) were used as outcome measures. OT added to antipsychotic treatment resulted in a significant improvement in positive symptoms, as measured by the PANSS total score, PANSS positive symptom subscale, PANSS negative symptom subscale, and the CGI. The effect size for these changes ranged from 0.40 for PANSS positive symptoms to 0.74 for the CGI. Furthermore, treatment with OT was well tolerated, with no significant differences between OT and placebo in rates of adverse effects nor in blood chemistry (Feifel et al. 2010). This same group published a second paper indicating an improvement in verbal memory in SCZ subjects following three weeks of twice daily OT (Feifel et al. 2012). The third study reports that two weeks of OT reduced psychotic symptoms and improved performance in a Theory of Mind task (Pedersen et al. 2011).