The quality of randomized controlled trials on DanShen in the treatment of ischemic vascular disease

Abstract

Background and objectives: Many randomized controlled trials (RCTs) were conducted to evaluate the efficacy of DanShen (Salvia miltiorrhizae, an herbal medicine) on ischemic vascular diseases (IVD). However, there has been no systematic evaluation of the quality of DanShen RCTs so far. The aims of this study were (1) to assess the quality of DanShen RCTs on IVD published in mainland China from 1998 to 2007 and (2) to explore the factors correlating with the quality.

Design: A number of Chinese databases were searched, and most of DanShen RCTs on IVD were collected. According to CONSORT for TCM (Consolidated Standards for Reporting of Trials for Traditional Chinese Medicine) and the Jadad scale, the quality assessment and data abstraction were performed independently by two reviewers. One-way analysis of variance and Pearson correlation analysis were applied to explore the association between basic characteristic and the quality of the RCTs.

Results: One hundred and fifty (150) DanShen RCTs were identified finally. The mean (standard deviation) score of 150 DanShen RCTs assessed by CONSORT for TCM was 23.87 (3.68), and 1.94 (0.82) by the Jadad scale, respectively. Only 6.7% (10/150) of RCTs were identified with high quality (Jadad score > or =4). Authors' affiliation, publication journal, sample size, and follow-up time were correlated with the quality of DanShen RCTs.

Conclusions: The quality of DanShen RCTs in mainland China has not been improved significantly over recent years, and the overall quality of DanShen RCTs is still poor.