title: Unit cohesion, traumatic exposure and mental health of military personnel.
abstract: BACKGROUND
  The benefit of military unit cohesion to morale and psychological resilience is well established. But it remains unclear whether unit cohesion modifies the association between deployment-related traumatic exposure and mental health problems.
  
  
  OBJECTIVE
  To examine the association between unit cohesion, traumatic exposure and poor mental health [symptoms of post-traumatic stress disorder (PTSD), psychological distress and alcohol dependency] and assess whether the relationship between traumatic exposure and poor mental health differs by level of unit cohesion.
  
  
  METHODS
  A self-reported cross-sectional survey of Australian military personnel deployed to Iraq or Afghanistan between 2001 and 2009.
  
  
  RESULTS
  Among 11411 participants, those with low levels of unit cohesion had higher odds of PTSD symptoms [aOR (95% CI): 2.54 (1.88, 3.42)], very high psychological distress [aOR (95% CI): 4.28 (3.04, 6.02)] and a high level of alcohol problems [aOR (95% CI): 1.71 (1.32, 2.22)] compared with those reporting high unit cohesion on deployment. Higher exposure to traumatic events on deployment was associated with greater risk of PTSD symptoms, very high levels of psychological distress and high levels of alcohol problems in this cohort. However, there was no evidence of a statistically significant interaction between unit cohesion and traumatic exposures in influencing poor mental health.
  
  
  CONCLUSIONS
  Our findings suggest that both unit cohesion and traumatic exposure are independently associated with poor mental health. Efforts to improve military unit cohesion may help to improve the mental health resilience of military personnel, regardless of their level of traumatic exposure.
authors.affiliation: School of Public Health, The University of Queensland, Brisbane, Queensland 4006, Australia, j.kanesarajah@uq.edu.au.
authors.forename: J
authors.initials: J
authors.lastname: Kanesarajah
authors.affiliation: School of Public Health, The University of Queensland, Brisbane, Queensland 4006, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Waller
authors.affiliation: Australian Institute of Health Innovation, Macquarie University, Sydney, New South Wales 2113, Australia.
authors.forename: W Y
authors.initials: WY
authors.lastname: Zheng
authors.affiliation: School of Public Health, The University of Queensland, Brisbane, Queensland 4006, Australia.
authors.forename: A J
authors.initials: AJ
authors.lastname: Dobson
mesh_terms: D000328:Adult; D055826:Afghan Campaign 2001-; D000437:Alcoholism / Q000209:etiology / Q000523:psychology; D003430:Cross-Sectional Studies; D003863:Depression / Q000209:etiology / Q000523:psychology; D005260:Female; D006801:Humans; D054542:Iraq War, 2003-2011; D008297:Male; D008875:Middle Aged; D008889:Military Personnel / Q000523:psychology*; D012189:Retrospective Studies; D013313:Stress Disorders, Post-Traumatic / Q000209:etiology / Q000523:psychology; D040921:Stress Disorders, Traumatic / Q000209:etiology* / Q000523:psychology; D011795:Surveys and Questionnaires
keywords: Alcohol problems; PTSD; military; psychological distress; traumatic exposure; unit cohesion.