Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Symptom severity
Systematic review	146 people Data from 1 RCT	Mean difference in Positive and Negative Syndrome Scale (PANSS) total score medium term with clozapine (250–600 mg/day, mean 345.7 mg/day) with ziprasidone (80–160 mg/day, mean 130.4 mg/day) Absolute results not reported	Mean difference –0.5 95% CI –7.72 to +6.72		Not significant