title: Issue in statistical strategy in case-control study.
authors.affiliation: Department of Infectious Diseases, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Xiang-Yong
authors.initials: XY
authors.lastname: Li
authors.affiliation: Department of Vascular Intervention, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Min-Jun
authors.initials: MJ
authors.lastname: Bai
authors.affiliation: Department of Gastroenterology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Lin-Jun
authors.initials: LJ
authors.lastname: Chen
authors.affiliation: Department of Hepatobiliary Surgery, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Jian-Liang
authors.initials: JL
authors.lastname: Xu
authors.affiliation: Department of Medical Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Zhi-Huan
authors.initials: ZH
authors.lastname: Lin
authors.affiliation: Department of Medical Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Xing
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Nephrology, Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, People's Republic of China.
authors.forename: Yan-Fang
authors.initials: YF
authors.lastname: Xing
mesh_terms: D001661:Biliary Tract Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D006528:Carcinoma, Hepatocellular / Q000453:epidemiology* / Q000473:pathology*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D008297:Male