Bishop 1964.

Methods	Allocation: random.                                                             Blinding: double. Duration: 10 weeks. Design: parallel (3 groups), single centre. Setting: inpatient, Toulane research wards, East Louisiana State Hospital, Jackson, Louisisana (USA).
Participants	Diagnosis: chronic schizophrenia. N = 42 *(n = 28 included in the analysis ‐ see interventions). Age: trifluoperazine ‐ mean 42.9 years; placebo ‐ mean 40.4 years; range 21‐53 years across both groups. Sex: 21M, 21F *(14M, 14F included in the analysis ‐ 7M, 7F in each group). Ethnicity: not stated. Consent: not stated. History: time hospitalised ranges from 3‐27 years, with a mean of 12.4 years for trifluoperazine and 11.7 in placebo groups. Included: off medication for at least 60 days and no committed to other projects. Excluded: concomitant physical or neurological disorder.
Interventions	1. Trifluoperazine: maximum dose 40 mg/day (week one: 5 mg/day; week two: 10 mg/day; week three: 20 mg/day; week four: 30 mg/day; weeks five‐10: 40 mg/day), n = 14. 2. Placebo: n = 14. *(3. Butaperazine: maximum dose 200 mg/day, n = 14 ‐ this group was not included in the analysis).
Outcomes	Global state: improvement (given as a single rating by averaging the final scores of four raters, using the Beckombergo Rating Scale; Psychotic Reactive Profile; Tulane Test Battery; and Minimal Social Behaviour scales). Extrapyramidal adverse effects: akathisia; dyskinesia; Parkinsonism‐like symptoms. Other adverse effects: lethargy; general adverse effects. Unable to use ‐ Global state: individual scores for BRS; PRP; TTB; and MSBS ‐ no mean or SD. Use of anti‐Parkinson drugs: half of the study population (n = 7 in each of the three groups of n = 14) received anti‐Parkinson medication as part of the treatment regimen from the beginning of the study until completion, therefore data are not presented as an effect of the study medication. Furthermore, no data were presented for the placebo group (selective reporting).
Notes	This study had an 'additional variable' (p675) of assessing the effect of the anti‐Parkinson medication Artane on half of the participants in each group (n = 7 from each group) with the remaining participants receiving an Artane placebo. No data were reported for the placebo group, only for the active drug groups.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomised ‐ quote “the 42 patients were divided randomly into three groups of 14, each containing 7 males and 7 females” (p674), no further details of randomisation methods.
Allocation concealment (selection bias)	Unclear risk	No description.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double ‐ quote, "all personnel involved in the project [remained] blind as to the medication a patient was receiving" (p675). Quote, “both drugs and placebo were supplied in capsules of identical appearance (Parke‐Davis No.2 pink) and were dispensed from individual medicine bottles” (p675).
Incomplete outcome data (attrition bias) All outcomes	Low risk	None detected.
Selective reporting (reporting bias)	High risk	For the 'additional variable' to this study, no data were reported for the placebo group regarding numbers of participants who experienced 'extrapyramidal reactions', only data for the active drug groups were presented. No statistical data reported.
Other bias	Unclear risk	Funding: supported by Public Health Grant 5 TI‐MH‐03701‐04 (Psychopharmacology Service Center, National Institute of Mental Health). Rating scales: raters not stated to be independent of treatment. Prinicpal investigator created the Tulane Test Battery scale utilised in the study.