title: Execution time determines the outcome of the multicenter randomized controlled trials.
abstract: OBJECTIVE
  Multicenter randomized controlled trials are the core of evidence-based medicine. Our study aimed to investigate the key factor which determined the outcome of the multicenter randomized controlled trials.
  
  
  METHODS
  We searched publications in PubMed for multicenter randomized controlled trials reporting primary data on treating and preventing cardiovascular diseases circulation area. The data were extracted from the including trials and used for analysis.
  
  
  RESULTS
  A total of 1075 trials for treating and preventing cardiovascular diseases were included, of which 979 were involved in the heart diseases and 96 involved in stroke. The execution time significantly contributed to the outcome of trials with shorter time related to significant outcome. However, the numbers of participated centers and their locations and participants had no effect on the outcome of trials. Moreover, the number of centers showed no significant relationship with execution time.
  
  
  CONCLUSIONS
  Execution time but not centers or participants contributed to the outcome of multicenter randomized controlled trials.
authors.affiliation: Department of Neurology, Jinling Hospital, Medical School of Nanjing University, 305 Zhongshan East Road, Nanjing 210002, China.
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Neurology, Jinling Hospital, Southern Medical University, 305 East Zhongshan Road, Nanjing 210002, Jiangsu, China; Department of Neurology, The Second People's Hospital of Huai'an and The Affiliated Huai'an Hospital of Xuzhou Medical University, 60 South Huaihai Road, Huai'an, Jiangsu, China.
authors.forename: Qijin
authors.initials: Q
authors.lastname: Zhai
authors.affiliation: Department of Neurology, Jinling Hospital, Medical School of Nanjing University, 305 Zhongshan East Road, Nanjing 210002, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Dai
authors.affiliation: Department of Neurology, Jinling Hospital, Medical School of Nanjing University, 305 Zhongshan East Road, Nanjing 210002, China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Neurology, Jinling Hospital, Medical School of Nanjing University, 305 Zhongshan East Road, Nanjing 210002, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Neurology, Jinling Hospital, Medical School of Nanjing University, 305 Zhongshan East Road, Nanjing 210002, China.
authors.forename: Zhuoyu
authors.initials: Z
authors.lastname: Wen
authors.affiliation: Department of Neurology, Jinling Hospital, Medical School of Nanjing University, 305 Zhongshan East Road, Nanjing 210002, China. Electronic address: xfliu2@vip.163.com.
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Liu
mesh_terms: D002318:Cardiovascular Diseases; D006801:Humans; D015337:Multicenter Studies as Topic; D017063:Outcome Assessment, Health Care; D016032:Randomized Controlled Trials as Topic; D012107:Research Design; D013997:Time Factors
keywords: Circulation; Clinical trials; Coronary artery disease; Multicenter; Randomized; Stroke