Article type
Year
Abstract
Background: Empirical evidence shows that, in general, studies with statistically significant results are more likely to be published than studies without statistically significant results (negative studies). Negative studies play a very important role in systematic reviews and meta-analysis.
Objectives: To investigate how many negative studies included in meta-analysis in China.
Methods: We searched Chinese Biomedical Literature database (CBM) which is considered Chinese MEDLINE from January 2009 to December 2011 and all meta-analysis of interventions were included. Each meta-analysis was independently identified and evaluated by two reviewers. We traced all studies included in meta-analysis we identified.
Results: Finally 967 Chinese meta-analysis were included. Three thousand seven hundred and four studies were traced back. Only one studies (0.02%) were negative studies.
Conclusions: Negative studies should be published both for scientific reasons and ethical reasons. Failure to identify negative studies would lead to publication bias. Chinese researchers and medical editors should publish more negative studies.
Objectives: To investigate how many negative studies included in meta-analysis in China.
Methods: We searched Chinese Biomedical Literature database (CBM) which is considered Chinese MEDLINE from January 2009 to December 2011 and all meta-analysis of interventions were included. Each meta-analysis was independently identified and evaluated by two reviewers. We traced all studies included in meta-analysis we identified.
Results: Finally 967 Chinese meta-analysis were included. Three thousand seven hundred and four studies were traced back. Only one studies (0.02%) were negative studies.
Conclusions: Negative studies should be published both for scientific reasons and ethical reasons. Failure to identify negative studies would lead to publication bias. Chinese researchers and medical editors should publish more negative studies.