Risk of bias tool in systematic reviews/meta-analyses of acupuncture in Chinese journals.

BACKGROUND

Use of a risk of bias (ROB) tool has been encouraged and advocated to reviewers writing systematic reviews (SRs) and meta-analyses (MAs). Selective outcome reporting and other sources of bias are included in the Cochrane ROB tool. It is important to know how this specific tool for assessing ROB has been applied since its release. Our objectives were to evaluate whether and to what extent the new Cochrane ROB tool has been used in Chinese journal papers of acupuncture.

METHODS

We searched CBM, TCM database, CJFD, CSJD, and the Wanfang Database from inception to March 2011. Two reviewers independently selected SRs that primarily focused on acupuncture and moxibustion, from which the data was extracted and analyzed.

RESULTS

A total of 836 SRs were identified from the search, of which, 105 were included and four are awaiting assessment. Thirty-six of the 105 SRs were published before release of the Cochrane ROB tool (up to 2009). Most used the Cochrane Handbook 4.2 or Jadad's scale for risk or quality assessment. From 2009 to March 2011 69 SRs were identified. While "risk of bias" was reported for approximately two-thirds of SRs, only two SRs mentioned use of a "risk of bias tool" in their assessment. Only 5.8% (4/69) of reviews reported information on all six domains which are involved in the ROB tool. A risk of bias graph/summary figure was provided in 2.9% (2/69) of reviews. Most SRs gave information about sequence generation, allocation concealment, blindness, and incomplete outcome data, however, few reviews (5.8%; 4/69) described selective reporting or other potential sources of bias.

CONCLUSIONS

The Cochrane "risk of bias" tool has not been used in all SRs/MAs of acupuncture published in Chinese Journals after 2008. When the ROB tool was used, reporting of relevant information was often incomplete.