Table 1.

PICOS criteria for study selection

Parameter	Inclusion	Exclusion
Patients	Diagnosis of schizophrenia according to the ICD/DSM criteria, any version Age ≥ 18 years
Intervention	Olanzapine monotherapy, any dose
Comparator	Placebo or other pharmacological treatments
Outcomes	Effect on the anxiety-related symptoms (measured by scores from clinical scales)	Absence of measurements concerning the anxiety dimension
Study design	double blind (db) RCT; post hoc analyses of dbRCTs

PICOS, Population, Intervention, Comparison, Outcomes and Study; ICD, International Classfication of Diseases; DSM, Diagnostic and Statistical Manual of Mental Disorders; RCT, randomized controlled trial.