About the Authors

Wu Jie

Contributed equally to this work with: Wu Jie, Zhou Xiaolan, Eileen Moyer

Affiliation Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China

Zhou Xiaolan

Contributed equally to this work with: Wu Jie, Zhou Xiaolan, Eileen Moyer

Affiliation Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China

Lu Ciyong

luciyong@yahoo.cn

Affiliation Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China

Eileen Moyer

Contributed equally to this work with: Wu Jie, Zhou Xiaolan, Eileen Moyer

Affiliation Amsterdam Institute of Social Science Research, Department of Sociology and Cultural Anthropology, University of Amsterdam, Amsterdam, The Netherlands

Wang Hui

Affiliation Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China

Hong Lingyao

Affiliation Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China

Deng Xueqing

Affiliation Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, China

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: LCY WJ ZXL. Performed the experiments: WJ ZXL. Analyzed the data: ZXL WJ. Contributed reagents/materials/analysis tools: DXQ. Wrote the paper: WJ. Obtained permission for use of the software used in analysis: WH HLY DXQ.