Kazamatsuri 1973.

Methods	Allocation: "randomly" Blindness: rater blind Duration: 24 weeks (4‐week antipsychotic and antiparkinsonism drug cessation and placebo administration, 18‐week intervention and then 2 weeks placebo) Design: parallel Setting: inpatients, USA
Participants	Diagnosis: chronic psychotic patients: chronic schizophrenia (10), mentally deficient (2), chronic brain syndrome (1); all manifesting typical buccolinguomasticatory oral dyskinesia associated with long‐term antipsychotic medication N = 13 Sex: 5 women and 8 men Age: mean 55.8 years, range 41‐63 years History: duration of TD not reported
Interventions	4 week washout from antiparkinsonism and antipsychotic medication (all replaced by placebo), then:. 1. haloperidol: dose 4 mg twice/d. From week 15 dose was doubled to 16 mg/d. N = 7 2. tetrabenazine: dose 50 mg twice/d. From week 15 onwards, dose was doubled to 200 mg/d. N = 6 Concomitant medications: "Other medications, such as antidiabetic or anticonvulsant drugs, were continued unchanged."
Outcomes	TD symptoms: not clinically improved TD symptoms: no improvement TD symptoms: deterioration Leaving the study early Unable to use ‐ TD scale scores and adverse effects: EPS Ward behaviour (NOSIE) (means, SDs not reported)
Notes	Sponsorship source: supported in part by Public Health Service grant from the National institute of Mental Health. Tetrabenazine and placebo tablets were provided by Hoffman‐La Roche.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"The 13 patients were divided randomly into two groups." further details not reported
Allocation concealment (selection bias)	Unclear risk	Allocation concealment not reported
Blinding of participants and personnel (performance bias) All outcomes	High risk	Blinding of participants and personnel not reported
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"A frequency count of mouth movements (18), done by a psychiatrist blind to the study design was used to assess oral dyskinesia."
Incomplete outcome data (attrition bias) All outcomes	High risk	2/7 (29%) participants dropped out from the haloperidol group; no further details are provided for addressing the outcomes of these participants. No participants dropped out from the tetrabenazine group.
Selective reporting (reporting bias)	High risk	TD scale scores and extrapyramidal symptoms scale scores not fully reported
Other bias	Unclear risk	Insufficient information to make a judgement