Itoh 1976.

Methods	Allocation: randomised. Blindness: double. Duration: 12 weeks, preceded by one week wash‐out. Setting: multi‐centre, Japan.
Participants	Diagnosis: schizophrenia (hebephrenia (n = 74), catatonia (n = 5), paranoid (n = 18) undifferentiated (n = 8)). N = 105. Age: range 19 to 50. Sex: 58 F, 47 M. History: inpatient; duration of hospitalisation of less than one year (n = 32), one to five years (n = 29), five years plus (n = 44); duration of illness range from less than one year to 10 years. Included: not clear. Excluded: somatic diseases; allergy; history of side effects of antiparkinsonians; glaucoma; prostate‐hypertrophy; children; pregnancy and older patients. Consent: not clear.
Interventions	1. Perphenazine: one tablet (a 4 mg) three times daily for the first week, 2 tablets three times daily in the second week, 3 tablets three times daily in the third week, then flexible dose according to the judgement of each physician; maximum 60 mg daily, n = 51. 2. Penfluridol: 1 tablet (a 20 mg) daily for the first week, 6 tablets in the second week, 9 tablets in the third week, then flexible dose according to the judgement of each physician; maximum 100 mg daily, n = 54.
Outcomes	Leaving the study early. Global state: no better or worse. Adverse events. Unable to use ‐ Mental state: BPRS (no SD), Keio University Psychiatric Rating Scale (unpublished scale).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomised: no further details.
Allocation concealment (selection bias)	Unclear risk	Not clear.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Double‐blind: no further details.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Not clear.
Selective reporting (reporting bias)	Unclear risk	Not clear.
Other bias	Unclear risk	Funding: not clear. Raters: not stated to be independent of treatment.