Background: Should we conduct more than one systematic review for the same topic or question? How many systematic reviews are similar between Chinese systematic reviews and Cochrane systematic reviews? Does it make sense for identified Cochrane systematic reviews that some authors still conducted the same systematic review?
Objectives: To detect the degree of similarity of systematic reviews between Chinese academic journals and the Cochrane Library.
Methods: We searched four of the main Chinese medical databases WANFANG, China National Knowledge Infrastructure/Chinese Academic Journals full text Database (CNKI), VIP (a full text database of China) and China Biomedicine Database (CBM); using the term 'systematic review’ or 'meta analysis' in the title from 1990 to 2010.
Results: We identified 2648 Chinese systematic reviews about healthcare. We conducted a comparative analysis of these systematic reviews with all Cochrane systematic reviews using the PICO method. We found that about 20% of Chinese systematic reviews were very similar to Cochrane systematic reviews. Most of them were published after the corresponding Cochrane systematic review. Further investigation is ongoing.
Conclusions: We will draw a distribution map between Chinese systematic reviews and Cochrane systematic reviews and identify blank and duplicate systematic reviews.