Abstract: AIM: To review the effectiveness of the safflor yellow injection (SYI) in the treatment for stable angina pectoris under the condition of large sample and deduction of multicentre effectiveness variation.METHODS: Four multicenter clinical trials (completed by 34 sub-centers with different efficacy) were collected.Each sub-center clinical trial was regarded as an independent study.According to our criteria, 25 suitable sub-centers were identified.A total of 1242 participants (787 participants in treatment group and 455 subjects in control group) were analyzed by Meta-analysis.Quality of included trials was assessed.Relative risk (RR) was used for the analysis of dichotomous outcomes, and the weighted mean difference (WMD) for continuous outcomes.Analysis of publication bias was shown with Fail-Safe number (N_fs).RESULTS: The effectiveness of SYI in treating stable angina pectoris were superior to control group, such as the efficacy of chest pain with pooled RR 1.25 and 95% CI 1.12 to 1.39, the chest distress with pooled RR 1.14 and 95% CI 1.06 to 1.22, the cardiopalmus with pooled RR 1.13, 95% CI 1.04 to 1.22, the effective rate of total scores of symptoms with pooled RR 1.21, and 95% CI 1.13 to 1.31, and the decrease of total scores of symptoms with pooled WMD 0.83 and 95% CI 0.55 to 1.12.The effective rates of chest pain, chest distress and cardiopalmus are 60%, 77.7% and 73.0%, respectively.It was 81.7% in total scores of symptoms.Fail-Safe number showed that the publication bias was not significant and the results were reliable.CONCLUSION: SYI is an effective agent for stable angina pectoris.This study also shows that if the result from each sub-center clinical trial is quite different or opposite, Meta-analysis can make decision about efficacy in multicentre clinical trial.

Key words: saffloryellowinjection(SYI), stableanginapectoris, Meta-analysis, multicentreclinicaltrial