Are randomized trials conducted in China or India biased? A comparative empirical analysis

China and India are two emerging forces in undertaking randomized clinical trials. The quality of trials from these countries may affect not just their substantial populations but also their contribution to health policy throughout the world.

The objectives of this study were to describe and contrast the quality and biases in reports of trials conducted in China and India with a set of "gold standard" trials reported in leading European and North American journals.

A systematic review and comparative empirical analysis of randomized controlled trial reports published in selected Chinese, Indian, and European or North American medical journals were performed. Quality was assessed against a subset of criteria from the CONSORT statement. We compared the rate of reporting of positive outcomes in clinical trials to describe potential bias.

In total, 307 Chinese papers, 117 Indian papers, and 304 Western papers were included. Reports of Indian trials were slightly better than Chinese papers on the trial reporting quality indicators and much better than Chinese papers on reporting patients' ethical issues. However, the gold standard Western trial reports scored considerably higher on all quality criteria. Chinese papers were substantially more likely to report statistically significant results (odds ratio [OR]=2.96, 95% confidence interval [CI]=2.23-3.94; P<0.0001). Indian trials reported a similar rate of positive results to Western papers (OR=0.92, 95% CI=0.69-1.24; P=0.59).

Reporting of trials in major Chinese and Indian journals falls short of that achieved in the gold standard Western journals we appraised and may reflect underlying inadequacies in the design and conduct of these trials. Chinese trials appear biased and may selectively report positive outcomes while ignoring neutral or negative outcomes. Trialists and journal editors in China and India should adopt the CONSORT reporting guidelines, should ensure that a primary outcome is prespecified and reported, and should ensure that analysis is conducted according to the intention-to-treat principle. Ethical questions in the conduct of trials in China must be addressed.