The study was financially supported by the National Basic Research Program (973 program) in China, and the trial protocol was registered in clinicaltrials.gov (NCT01201642).
The authors appreciate the help from participants to all staff who participated in this study, we especially thank the staff in Clinical Evaluation Center of China Academy of Chinese medical sciences for their help in data monitoring and statistical analysis. The study is financially supported by the National Basic Research Program of China (973 Program, no. 2011CB505200). Ying Li and Bing Zhu have full access to all of the data in the study; they take full responsibility for the integrity of the data and the accuracy of the data analysis. They have control of the decision to publish this study. The sponsor had no role in the design of the study, the collection, analysis, or interpretation of the data, the writing of the manuscript, or the decision to submit the article for publication.
