OBJECTIVES: Data were extracted independently from included papers by at least two review authors. Risk ratios (RR) and 95% confidence intervals (CI) of homogeneous dichotomous data were calculated. We assessed risk of bias for included studies and used GRADE to judge quality of evidence.
MAIN RESULTS: We could only include five studies conducted between 1965 and 1980. Most of the included studies did not report details of randomisation, allocation concealment, details of blinding and we could not assess the impact of attrition due to poor reporting.For the primary outcome of Global state - not improved, the confidence interval was compatible with a small benefit and increased risk of not improving with
pericyazine compared with typical
antipsychotics (2 RCTs, n = 122, RR 1.24 CI 0.93 to 1.66, very low quality of evidence) or atypical
antipsychotics (1 RCT, n = 93, RR 0.97 CI 0.67 to 1.42, very low quality of evidence).When compared with typical
antipsychotics relapse was only experienced by one person taking
pericyazine (1 RCT, n = 80, RR 2.59 CI 0.11 to 61.75, very low quality of evidence).
Pericyazine was associated with more extrapyramidal side effects than typical
antipsychotics (3 RCTs, n = 163, RR 0.52 CI 0.34 to 0.80, very low quality of evidence) and atypical
antipsychotics (1 RCT, n = 93, RR 2.69 CI 1.35 to 5.36, very low quality of evidence).The estimated risk of leaving the study early for specific reasons was imprecise for the comparisons of
pericyazine with typical
antipsychotics (2 RCTs, n = 71, RR 0.46 CI 0.11 to 1.90, very low quality of evidence), and with atypical
antipsychotics (1 RCT, n = 93, RR 0.13 CI 0.01 to 2.42, very low quality of evidence).
AUTHORS' CONCLUSIONS: On the basis of very low quality evidence we are unable to determine the effects of
pericyazine in comparison with typical or atypical
antipsychotics for the treatment of
schizophrenia. However, there is some evidence that
pericyazine may be associated with a higher incidence of extrapyramidal side effects than other
antipsychotics, and again this was judged to be very low quality evidence. Large, robust studies are still needed before any firm conclusions can be drawn.