title: Exploration of statistical shrinkage parameters of disproportionality methods in spontaneous reporting system of China.
abstract: OBJECTIVE
  Statistical shrinkage is a potential statistical method to improve the accuracy of signal detection results and avoid spurious associations detected by disproportionality analyses. In this study, we introduced statistical shrinkage influence on disproportionality methods in spontaneous reporting system in China.
  
  
  METHODS
  We added the shrinkage parameters in the numerator and denominator, denoted as in the formula of disproportionality analysis. The shrinkage parameters were subjectively set to between 0 and 5, with an interval of 0.1. Adverse drug reaction product label database was deemed as a proxy of golden standard to evaluate the effect of statistical shrinkage. Reports in the years of 2010-2011 were extracted from the national spontaneous reporting system database as the data source for analysis in this study.
  
  
  RESULTS
  When α was around 0.5, the Youden index reached the maximum for each disproportionality methods in this study. The value of 0.6 was suggested as the most appropriate statistical shrinkage parameter for reporting odds ratio and proportional reporting ratio and 0.2 for information component based on the spontaneous reporting system of China.
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Xiao-Fei
authors.initials: XF
authors.lastname: Ye
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Xiao-Jing
authors.initials: XJ
authors.lastname: Guo
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Tian-Tian
authors.initials: TT
authors.lastname: Zhu
authors.affiliation: Kidney Institute of CPLA, Division of Nephrology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, China.
authors.forename: Na
authors.initials: N
authors.lastname: Qi
authors.affiliation: National Center for ADR Monitoring, Beijing, 100045, China.
authors.forename: Yong-Fang
authors.initials: YF
authors.lastname: Hou
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Tian-Yi
authors.initials: TY
authors.lastname: Zhang
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Wen-Tao
authors.initials: WT
authors.lastname: Shi
authors.affiliation: School of Medicine, Shanghai Jiao Tong University, Shanghai, 200025, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wei
authors.affiliation: School of Medicine, Shanghai Jiao Tong University, Shanghai, 200025, China.
authors.forename: Yu-Zhou
authors.initials: YZ
authors.lastname: Liu
authors.affiliation: National Center for ADR Monitoring, Beijing, 100045, China.
authors.forename: Gui-Zhi
authors.initials: GZ
authors.lastname: Wu
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China.
authors.forename: Jia
authors.initials: J
authors.lastname: He
mesh_terms: D016907:Adverse Drug Reaction Reporting Systems / Q000706:statistics & numerical data*; D000465:Algorithms; D002681:China / Q000453:epidemiology; D016208:Databases, Factual / Q000706:statistics & numerical data*; D064420:Drug-Related Side Effects and Adverse Reactions / Q000453:epidemiology; D006801:Humans; D016017:Odds Ratio; D060735:Pharmacovigilance
keywords: adverse drug reaction; false positive signal; pharmacoepidemiology; pharmacovigilance; signal detection; statistical shrinkage