https://aub.ie/MilitaryREACH-Campbell-Sills2022

Campbell-Sills, L., Flynn, P. J., Choi, K. W., Ng, T. H. H., Aliaga, P. A., Broshek, C., Jain, S…Bliese, P. D. (2022). Unit cohesion during deployment and post-deployment mental health: Is cohesion an individual- or unit-level buffer for combat-exposed soldiers? Psychological Medicine, 52, 121-131. https://doi.org/10.1017/S0033291720001786

This study examined the role of unit cohesion in protecting both Soldiers and units against the negative impact of combat exposure on mental health. The study used administrative records as well as longitudinal data, provided by Soldiers following a deployment (N = 6,888 from 89 units), regarding their perceptions of vertical (subordinate-to-leader) and horizontal (peer-to-peer) unit cohesion, combat experiences, and mental health. Individual and unit-wide assessments (i.e., average scores from members of the same unit) were analyzed. Individual perceptions of horizontal unit cohesion buffered against the negative impact of combat exposure on post-deployment posttraumatic stress disorder (PTSD) and depression; the same trend was observed at the unit-level. Notably, unit-wide horizontal cohesion does not appear to have the same protective effect against unit suicidal ideation when collective combat exposure is high within the unit.

https://doi.org/10.1017/S0033291720001786

Deployment
Mental health

Army

Active Duty

Active duty service member

Young adulthood (18 - 29 yrs)
Adulthood (18 yrs & older)
Thirties (30 - 39 yrs)
Middle age (40 - 64 yrs)

Quantitative Study
Longitudinal Study

Campbell-Sills, Laura, Flynn, Patrick J., Choi, Karmel W., Ng, Tsz Hin H., Aliaga, Pablo A., Broshek, Catherine, Jain, Sonia, Kessler, Ronald C., Stein, Murray B., Ursano, Robert J., Bliese, Paul D.

BACKGROUND: Unit cohesion may protect service member mental health by mitigating effects of combat exposure; however, questions remain about the origins of potential stress-buffering effects. We examined buffering effects associated with two forms of unit cohesion (peer-oriented horizontal cohesion and subordinate-leader vertical cohesion) defined as either individual-level or aggregated unit-level variables. METHODS: Longitudinal survey data from US Army soldiers who deployed to Afghanistan in 2012 were analyzed using mixed-effects regression. Models evaluated individual- and unit-level interaction effects of combat exposure and cohesion during deployment on symptoms of post-traumatic stress disorder (PTSD), depression, and suicidal ideation reported at 3 months post-deployment (model n's = 6684 to 6826). Given the small effective sample size (k = 89), the significance of unit-level interactions was evaluated at a 90% confidence level. RESULTS: At the individual-level, buffering effects of horizontal cohesion were found for PTSD symptoms [B = -0.11, 95% CI (-0.18 to -0.04), p < 0.01] and depressive symptoms [B = -0.06, 95% CI (-0.10 to -0.01), p < 0.05]; while a buffering effect of vertical cohesion was observed for PTSD symptoms only [B = -0.03, 95% CI (-0.06 to -0.0001), p < 0.05]. At the unit-level, buffering effects of horizontal (but not vertical) cohesion were observed for PTSD symptoms [B = -0.91, 90% CI (-1.70 to -0.11), p = 0.06], depressive symptoms [B = -0.83, 90% CI (-1.24 to -0.41), p < 0.01], and suicidal ideation [B = -0.32, 90% CI (-0.62 to -0.01), p = 0.08]. CONCLUSIONS: Policies and interventions that enhance horizontal cohesion may protect combat-exposed units against post-deployment mental health problems. Efforts to support individual soldiers who report low levels of horizontal or vertical cohesion may also yield mental health benefits.

Cambridge University Press

Article
REACH Publication

Department of Psychiatry, University of California San Diego, LCS
Department of Psychiatry, University of California San Diego, MBS
Department of Management, Innovation, and Entrepreneurship, Poole College of Management, North Carolina State University, PJF
Department of Psychiatry, Massachusetts General Hospital, KWC
Department of Epidemiology, Harvard T.H. Chan School of Public Health, KWC
Psychiatric and Neurodevelopmental Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, KWC
Stanley Center for Psychiatric Research, Broad Institute, KWC
Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences, THHN
Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences, PAA
Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences, CB
Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences, RJU
Henry M. Jackson Foundation for the Advancement of Military Medicine, THHN
Henry M. Jackson Foundation for the Advancement of Military Medicine, PAA
Henry M. Jackson Foundation for the Advancement of Military Medicine, CB
Department of Family Medicine and Public Health, University of California San Diego, SJ
Department of Family Medicine and Public Health, University of California San Diego, MBS
Department of Health Care Policy, Harvard Medical School, RCK
VA San Diego Healthcare System, MBS
Department of Management, Darla Moore School of Business, University of South Carolina, PDB