title: Changes of anxiety in Chinese military personnels over time: a cross-temporal meta-analysis.
abstract: BACKGROUND
  Previous cross-temporal meta-analyses have demonstrated that anxiety would get severer over time. The changes of anxiety in Chinese military personnels over time remain unclear.
  
  
  OBJECTIVE
  To explore the changes of anxiety in Chinese military personnels over nearly past two decades.
  
  
  METHODS
  Studies using the Chinese version of Spielberger's State-Trait Anxiety Inventory (STAI) in Chinese serviceman on active duty were primarily collected. Mean, standard deviation and sample size of each study were extracted for meta-analysis. With sample size of each study as weighted least-squares weight, we regressed the mean scores on the data collection year to evaluate changes in anxiety from 1991 to 2011. Correlations between the anxiety scores and some social indicators were also examined.
  
  
  RESULTS
  The final sample consisted of 45 separate studies with a total of 18,106 participants for state anxiety and 21,047 participants for trait anxiety. Both state anxiety and trait anxiety significantly increased over the past two decades. The effect sizes for state anxiety and trait anxiety were 0.88 and 0.63, respectively. Anxiety scores were significantly correlated with some social indicators (e.g., crime rate, unemployment rate) of the corresponding years or 5 years prior to the anxiety data collection.
  
  
  CONCLUSIONS
  Some measures must be taken to tackle the problem of the rising anxiety scores. Given that Chinese military personnels are continuing to experience high levels of anxiety, it is crucial to consider the implications for mental health care and treatment. More cross-temporal meta-analyses are needed to examine the changes of mental health in Chinese military personnels over time.
authors.affiliation: Department of Psychology, Fourth Military Medical University, Chang Le Western Street No.169, Xi'an Shaanxi Co. 710032, China.
authors.forename: Zhibing
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Psychology, Fourth Military Medical University, Chang Le Western Street No.169, Xi'an Shaanxi Co. 710032, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Cao
authors.affiliation: Department of Psychology, Fourth Military Medical University, Chang Le Western Street No.169, Xi'an Shaanxi Co. 710032, China.
authors.forename: Huijie
authors.initials: H
authors.lastname: Lu
authors.affiliation: Department of Psychology, Fourth Military Medical University, Chang Le Western Street No.169, Xi'an Shaanxi Co. 710032, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Department of Psychology, Fourth Military Medical University, Chang Le Western Street No.169, Xi'an Shaanxi Co. 710032, China.
authors.forename: Danmin
authors.initials: D
authors.lastname: Miao
keywords: Anxiety; Cross-temporal meta-analysis; Military