Parent 1983.

Methods	Randomisation: “treated at random”. Blinding: “open” study (not double‐blind). Duration: 28 days. Design: parallel.  Location: not indicated. Setting: inpatients.
Participants	Diagnosis: schizophrenic psychosis: simple type (N = 11), paranoid type (N = 4), schizo‐affective type (N = 2), acute schizophrenic episode (N = 1), latent schizophrenia (N = 1), residual schizophrenia (N = 1), specific reading retardation (N = 1). N = 21. Gender (N = 40): 21M, 19F. Age: mean 43.4 years. History: duration stable: not indicated, duration of illness: not indicated, number of previous hospitalisations: not indicated, age at onset: not indicated, severity of illness: "a score of 23 or more on the Psychiatrists´ Clinical Global Impression Rating”, baseline antipsychotic dose: not indicated.
Interventions	1. Haloperidol: fixed/flexible dose: not indicated, dose range: 8 mg to 50 mg/day, mean dose: 21.1 mg/day. N = 10. 2. Flupenthixol: fixed/flexible dose: not indicated, dose range: 32 mg to 192 mg/day, mean dose: 111.3 mg/day. N = 11.   Rescue medication: “If there were any extrapyramidal side‐effects, procyclidine might be given, and, if necessary, a benzodiazepine might be administered at night.” “During the first period of treatment dosage was titrated to the optimum. Initial dosage was determined by the severity of disease and by the age of the patient.”
Outcomes	Examined: Clinically important response to treatment: “modification of the Psychiatrists´Clinical Global Impression”. Mental state general: Brief Psychiatric Rating Scale (BPRS). Leaving the study early due to any reason. Adverse effects: at least one movement disorder, use of antiparkinson medication. Unable to use: Behaviour: Nurses` Clinical Impression (no raw data available).
Notes	The whole sample size of the trial included 40 participants (21 with schizophrenic psychosis, 13 with manic‐depressive psychosis and 6 with paranoid states). The results of the psychiatric assessments were provided separately for the 21 schizophrenic participants. Study participants were 21 participants with acute schizophrenic psychosis (“acutely psychotic patients"). 7 participants with first episode.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Allocation through “randomisation”. No further details.
Allocation concealment (selection bias)	Unclear risk	No further details.
Blinding (performance bias and detection bias) (performance bias)	High risk	“The study was open”.
Blinding (performance bias and detection bias) (detection bias)	High risk	“The study was open”.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The overall‐attrition was rather low (2 of 21 participants, 9.5%). One participant in each treatment group left the trial early. Although it was not explicitly mentioned which type of analysis was used for the BPRS, it was not  considered as bias because of the low drop‐out rate in each treatment group.
Selective reporting (reporting bias)	Unclear risk	Raw data of the Nurses` Clinical Impression scale were not reported; but this was not relevant for the outcomes of interest in this systematic review. Adverse effects reporting was incomplete.
Other bias	High risk	A high dosage of flupenthixol was compared to conventional dosages of haloperidol. This can be considered as potential bias. Administration of benzodiazepines in 9 participants of each treatment group. “1 patient in each group was treated with an additional neuroleptic.” “There was some imbalance between the treatment groups with regard to previous acute episodes.”