Various drugs 1975.

Study characteristics
Methods	Randomisation: random, in blocks of eight, stratified for age, duration ill and time since last admission. Allocation: procedure not described. Blinding: double‐blind, identical capsules, each participant had an individual stock bottle. Duration: 24 weeks. Design: parallel. Location: single‐centre. Setting: outpatient.
Participants	Diagnosis: chronic schizophrenia (clinical diagnosis), 22 undifferentiated, 7 paranoid, 1 schizoaffective, no severe other psychiatric or somatic illnesses, no severely ill participants. N = 40. Gender: 40 women. Age: mean 42.8 years (range 24 to 60). History: duration stable‐ maintained on medication in an outpatient status for at least 3 months, "relatively stable state of health”, duration ill‐ mean 11.6 years, number of previous hospitalisations‐ mean 6.1, age at onset ‐ NI, severity of illness‐ mean CGI severity score 2.94, baseline antipsychotic dose‐ n.i..
Interventions	1. Drug: pimozide.* Flexible dose. Allowed dose range: 2 mg/day to 20 mg/day. Mean dose: 5.3 mg/day. N = 15. 2. Drug: thioridazine.* Flexible dose. Allowed dose range: 75 mg/day to 750 mg/day. Mean dose: 189 mg/day. N = 15. 3. Placebo: duration of taper: 0 days. N = 10. Rescue medication: antiparkinson medication, bedside sedation.
Outcomes	Examined Relapse (worsening of global state). Leaving the study early. Global state: number of participants improved (CGI based). Global state ‐ number of participants in remission (CGI based) Adverse effects: binary outcomes ‐ open interview. Unable to use/Not included Mental state: BPRS (no SD/no prespecified outcome of interest). Functioning: Katz Lyerly Scale of Social Adjustment, Patient Rating Form, Family Rating Form (no data available ) Physiological measures: biological parameters (temperature, mean weight, pulse, blood pressure, all no data/all no prespecified outcomes of interest), laboratory (blood count, urine analysis, liver enzymes, blood sugar, protein bound iodine, all no prespecified outcomes of interest).
Notes	* The results of pimozide and thioridazine were combined in the analysis.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random, in blocks of eight, stratified for age, duration ill and time since last admission.
Allocation concealment (selection bias)	Unclear risk	Procedure not described.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Double‐blind, identical capsules, each participant had an individual stock bottle.
Blinding (performance bias and detection bias) Subjective outcomes	Unclear risk	Double‐blind, identical capsules, each participant had an individual stock bottle.
Blinding (performance bias and detection bias) Objective outcomes	Low risk	Double‐blind, identical capsules, each participant had an individual stock bottle.
Incomplete outcome data (attrition bias) All outcomes	High risk	Overall 36% left the study early. The specific reasons why the participants dropped out were not indicated by group.
Selective reporting (reporting bias)	Low risk	No clear source for selective reporting.
Other bias	Low risk	No clear other sources of bias.