[1] Southern Med Univ, Nanfang Hosp, Dept Plast & Reconstruct Surg, Guangzhou 510515, Guangdong, Peoples R China
[2] Nippon Med Sch, Dept Plast Reconstruct & Aesthet Surg, Tokyo 113, Japan
[3] Southern Med Univ, Sch Publ Hlth & Trop Med, Dept Biostat, Guangzhou 510515, Guangdong, Peoples R China