1 National Clinical Research Centre for Kidney Disease, State Key Laboratory of Organ Failure Research, Department of Biostatistics, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, Guangdong, P.R. China.
2 Department of Biostatistics, Bioinformatics & Biomathematics, Georgetown University Medical Center, 4000 Reservoir Rd NW, Washington DC, USA. ming.tan@georgetown.edu.
3 National Clinical Research Centre for Kidney Disease, State Key Laboratory of Organ Failure Research, Department of Biostatistics, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, Guangdong, P.R. China. chenpy99@126.com.