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Combat Deployment Is Associated with Sexual Harassment or Sexual Assault in a Large, Female Military Cohort

      Abstract

      Background

      Previous studies have examined the prevalence, risk factors, and health correlates of sexual stressors in the military, but have been limited to specific subpopulations. Furthermore, little is known about sexual stressors' occurrence and their correlates in relation to female troops deployed to the current operations in Iraq and Afghanistan.

      Methods

      Using longitudinal data from Millennium Cohort participants, the associations of recent deployment as well as other individual and environmental factors with sexual harassment and sexual assault were assessed among U.S. female military personnel. Multivariable analyses were used to investigate the associations.

      Findings

      Of 13,262 eligible participants, 1,362 (10.3%) reported at least one sexual stressor at follow-up. Women who deployed and reported combat experiences were significantly more likely to report sexual harassment (odds ratio [OR], 2.20; 95% confidence interval [CI], 1.84–2.64) or both sexual harassment and sexual assault (OR, 2.47; 95% CI, 1.61–3.78) compared with nondeployers. In addition, significant risk factors for sexual stressors included younger age, recent separation or divorce, service in the Marine Corps, positive screen for a baseline mental health condition, moderate/severe life stress, and prior sexual stressor experiences.

      Conclusions

      Although deployment itself was not associated with sexual stressors, women who both deployed and reported combat were at a significantly increased odds for sexual stressors than other female service members who did not deploy. Understanding the factors associated with sexual stressors can inform future policy and prevention efforts to eliminate sexual stressors.

      Introduction and Background

      Unwanted sexual experiences have been associated with poor mental and physical health (
      • Campbell R.
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      Gynecological health impact of sexual assault.
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      Sexual assault while in the military: Violence as a predictor of cardiac risk?.
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      Functioning and psychiatric symptoms among military men and women exposed to sexual stressors.
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      Posttraumatic stress symptomatology as a mediator of the association between military sexual trauma and post-deployment physical health in women.
      ), including posttraumatic stress disorder (PTSD;
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      Gender differences in rates of depression, PTSD, pain, obesity, and military sexual trauma among Connecticut War Veterans of Iraq and Afghanistan.
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      • Cronkite R.C.
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      Military-related sexual trauma among Veterans Health Administration patients returning from Afghanistan and Iraq.
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      ,
      • Vogt D.S.
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      • King L.A.
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      Deployment stressors, gender, and mental health outcomes among Gulf War I veterans.
      ) and unhealthy behaviors, such as alcohol abuse (
      • Davis T.M.
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      Substance abuse and sexual trauma in a female veteran population.
      ,
      • Gradus J.L.
      • Street A.E.
      • Kelly K.
      • Stafford J.
      Sexual harassment experiences and harmful alcohol use in a military sample: Differences in gender and the mediating role of depression.
      ). The issue of sexual harassment and sexual assault in the military has recently started to receive more attention from researchers (
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      Military sexual trauma: A review of prevalence and associated health consequences in veterans.
      ), the Department of Defense (
      • Lipari R.N.
      • Cook P.J.
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      • Matos K.
      2006 Gender relations survey of active duty members.
      ,
      • Lipari R.N.
      • Lancaster A.R.
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      2004 Sexual harassment survey of reserve component members.
      ), and media (
      • La Bash H.A.
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      • King D.W.
      Deployment stressors of the Iraq War: Insights from the mainstream media.
      ,

      Risen, J. (2012, November 2). Military has not solved problem of sexual assault, women say. The New York Times. Retrieved from http://www.nytimes.com/2012/11/02/us/women-in-air-force-say-sexual-misconduct-still-rampant.html?pagewanted=all.

      ). A recent, nationally representative survey of active duty U.S. military personnel found that 4.4% of women and 0.9% of men reported unwanted sexual contact in the past year (
      • Rock L.M.
      • Lipari R.N.
      • Cook P.J.
      • Hale A.D.
      2010 workplace and gender relations survey of active duty members: overview report on sexual assault.
      ). Rates of sexual harassment are higher, with 34% of women and 6% of men reporting these experiences (
      • Lipari R.N.
      • Cook P.J.
      • Rock L.M.
      • Matos K.
      2006 Gender relations survey of active duty members.
      ). Among female veterans of the Iraq and Afghanistan wars who received health care in the Veterans Administration Health Care System, military sexual trauma rates are as high as 15% (
      • Haskell S.G.
      • Gordon K.S.
      • Mattocks K.
      • Duggal M.
      • Erdos J.
      • Justice A.
      • et al.
      Gender differences in rates of depression, PTSD, pain, obesity, and military sexual trauma among Connecticut War Veterans of Iraq and Afghanistan.
      ,
      • Kimerling R.
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      • Pavao J.
      • Smith M.W.
      • Cronkite R.C.
      • Holmes T.H.
      • et al.
      Military-related sexual trauma among Veterans Health Administration patients returning from Afghanistan and Iraq.
      ). Furthermore, in previously deployed veterans, sexual harassment and sexual assault were suggestive of declines in postdeployment health and increase use of Veterans Affairs services (
      • Bean-Mayberry B.
      • Yano E.M.
      • Washington D.L.
      • Goldzweig C.
      • Batuman F.
      • Huang C.
      • et al.
      Systematic review of women veterans' health: update on successes and gaps. [Research Support, Non-U.S. Gov't Review].
      ,
      • Vogt D.S.
      • Pless A.P.
      • King L.A.
      • King D.W.
      Deployment stressors, gender, and mental health outcomes among Gulf War I veterans.
      ,
      • Wolfe J.
      • Schnurr P.P.
      • Brown P.J.
      • Furey J.
      Posttraumatic stress disorder and war-zone exposure as correlates of perceived health in female Vietnam War veterans.
      ). Among recent war veterans with PTSD, women who experienced military sexual trauma had more comorbid mental health diagnoses than those who did not experience military sexual trauma (
      • Maguen S.
      • Cohen B.
      • Ren L.
      • Bosch J.
      • Kimerling R.
      • Seal K.
      Gender differences in military sexual trauma and mental health diagnoses among Iraq and Afghanistan veterans with posttraumatic stress disorder.
      ). Although research efforts have examined sexual stressors in military populations, these have been limited to specific subgroups (e.g., veterans, active duty Air Force women) and constrained by retrospective or cross-sectional designs (
      • Bostock D.J.
      • Daley J.G.
      Lifetime and current sexual assault and harassment victimization rates of active-duty United States Air Force women.
      ,
      • Kimerling R.
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      • Pavao J.
      • Smith M.W.
      • Cronkite R.C.
      • Holmes T.H.
      • et al.
      Military-related sexual trauma among Veterans Health Administration patients returning from Afghanistan and Iraq.
      ,
      • Martin L.
      • Rosen L.N.
      • Durand D.B.
      • Stretch R.H.
      • Knudson K.H.
      Prevalence and timing of sexual assaults in a sample of male and female U.S. Army soldiers.
      ,
      • Street A.E.
      • Gradus J.L.
      • Stafford J.
      • Kelly K.
      Gender differences in experiences of sexual harassment: Data from a male-dominated environment.
      ). To our knowledge, no study has examined the relationship between deployment and sexual stressors with the operations in Iraq and Afghanistan among a population-based sample of U.S. female service members. Understanding this relationship is imperative to help design interventions and guide future policy, and to reduce the presence of these stressors in the military.
      The Millennium Cohort Study, a population-based cohort of U.S. service members, provides a unique opportunity to examine this association between deployment to the recent conflicts and sexual stressors, while rectifying some previous research deficiencies (
      • Gray G.C.
      • Chesbrough K.B.
      • Ryan M.A.
      • Amoroso P.
      • Boyko E.J.
      • Gackstetter G.D.
      • et al.
      The Millennium Cohort Study: A 21-year prospective cohort study of 140,000 military personnel.
      ,
      • Ryan M.A.
      • Smith T.C.
      • Smith B.
      • Amoroso P.
      • Boyko E.J.
      • Gray G.C.
      • et al.
      Millennium Cohort: Enrollment begins a 21-year contribution to understanding the impact of military service.
      ). Thus, the study's main objective was to investigate deployment as well as other individual and environmental factors in relation to sexual harassment and sexual assault among U.S. military women.

      Methods

      Study Population

      The Millennium Cohort Study, a large longitudinal study, was launched in 2001 to investigate health outcomes associated with military service (
      • Gray G.C.
      • Chesbrough K.B.
      • Ryan M.A.
      • Amoroso P.
      • Boyko E.J.
      • Gackstetter G.D.
      • et al.
      The Millennium Cohort Study: A 21-year prospective cohort study of 140,000 military personnel.
      ,
      • Ryan M.A.
      • Smith T.C.
      • Smith B.
      • Amoroso P.
      • Boyko E.J.
      • Gray G.C.
      • et al.
      Millennium Cohort: Enrollment begins a 21-year contribution to understanding the impact of military service.
      ). Using an in-depth questionnaire, occupational and life experiences are assessed prospectively at 3-year intervals. The cohort currently includes more than 150,000 members who enrolled during three separate cycles between 2001 and 2008. The methodology of the Millennium Cohort Study has been described previously (
      • Ryan M.A.
      • Smith T.C.
      • Smith B.
      • Amoroso P.
      • Boyko E.J.
      • Gray G.C.
      • et al.
      Millennium Cohort: Enrollment begins a 21-year contribution to understanding the impact of military service.
      ,
      • Smith T.C.
      The US Department of Defense Millennium Cohort Study: Career span and beyond longitudinal follow-up.
      ). This study population included women from the first panel, who provided informed consent, completed a baseline (2001–2003) and first follow-up questionnaire (2004–2006), and had complete data. Because the focus of this study was to examine the possible association between deployment and sexual stressors, those who were separated from the U.S. military before baseline were excluded.

      Sexual Stressors Metrics

      At the 2004–2006 follow-up assessment, participants were asked if they “suffered forced sexual relations or sexual assault” or “experienced sexual harassment” in the past 3 years. Based on their responses, participants were classified into one of four possible categories: a) Sexual assault and sexual harassment, b) sexual assault only, c) sexual harassment only, or d) no sexual stressor.
      At the 2001–2003 baseline assessment, participants were also asked if they had “ever” experienced these events. Participants responding “yes” to either or both events were classified as having prior sexual stressors.

      Deployment and Combat Experience

      Deployment was ascertained from Department of Defense electronic military data documenting in and out of theater dates for personnel in support of the operations in Iraq and Afghanistan. Based on these files received from the Defense Manpower Data Center, the main exposure was deployment between baseline and follow-up. Because it has been demonstrated that combat experience increases the risk for postdeployment adverse health outcomes (
      • Hoge C.W.
      • Castro C.A.
      • Messer S.C.
      • McGurk D.
      • Cotting D.I.
      • Koffman R.L.
      Combat duty in Iraq and Afghanistan, mental health problems, and barriers to care.
      ,
      • Smith T.C.
      • Ryan M.A.
      • Wingard D.L.
      • Slymen D.J.
      • Sallis J.F.
      • Kritz-Silverstein D.
      • et al.
      New onset and persistent symptoms of post-traumatic stress disorder self reported after deployment and combat exposures: Prospective population based US military cohort study.
      ), participants were categorized as nondeployed, deployed without combat-like experiences, or deployed with combat-like experiences. Participants were considered to have deployed with combat-like experiences if they reported personal exposure at follow-up to at least one of the following: witnessing death; witnessing physical abuse; dead and/or decomposing bodies; maimed soldiers or civilians; or prisoners of war, or refugees. To control for earlier deployments, women who deployed before baseline, including 1) the 1991 Gulf War, 2) Bosnia, Kosovo, or Southwest Asia between 1998 and 2000, or 3) in support of the operations in Iraq and Afghanistan, were classified as having previous deployment experience.

      Individual Vulnerability Factors

      Problem drinking was assessed using baseline questions from the Primary Care Evaluation of Mental Disorders Patient Health Questionnaire (PHQ). Participants who reported one or more of five alcohol-related problems in the last 12 months, such as driving a car after several drinks, were classified as having alcohol-related problems. At baseline, women who reported drinking more than seven alcoholic drinks per week were considered to be heavy drinkers, and those consuming four or more drinks per occasion or day were considered binge drinkers, based on research indicating that drinking beyond this level may increase the risk for alcohol-related problems (
      • Criqui M.H.
      Do known cardiovascular risk factors mediate the effect of alcohol on cardiovascular disease?.
      ,
      • Dawson D.A.
      • Grant B.F.
      • Li T.K.
      Quantifying the risks associated with exceeding recommended drinking limits.
      ,
      • Goldberg I.J.
      • Mosca L.
      • Piano M.R.
      • Fisher E.A.
      AHA Science Advisory: Wine and your heart: a science advisory for healthcare professionals from the Nutrition Committee, Council on Epidemiology and Prevention, and Council on Cardiovascular Nursing of the American Heart Association.
      ,
      • Naimi T.S.
      • Brewer R.D.
      • Mokdad A.
      • Denny C.
      • Serdula M.K.
      • Marks J.S.
      Binge drinking among US adults.
      ,
      • U.S. Department of Health and Human Services and U.S. Department of Agriculture
      Dietary Guidelines for Americans, 2005, 6th ed.
      ).
      Baseline mental health status was assessed using data from the PTSD Checklist-Civilian Version (PCL-C) and the PHQ. Based on the 17 self-reported PCL-C items, participants were identified as screening positive for PTSD if they reported a moderate or higher level of at least one intrusion symptom, three avoidance symptoms, and two hyperarousal symptoms (criteria established by the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision [DSM-IV-TR];
      American Psychiatric Association
      Diagnostic and statistical manual of mental disorders 4th ed, text revision.
      ,

      Weathers, F. W., Litz, B. T., Herman, D. S., Huska, J. A., & Keane, T. M. (1993October). The PTSD Checklist (PCL): reliability, validity, and diagnostic utility. Paper presented at the Paper presented at the Annual Meeting of International Society for Traumatic Stress Studies, San Antonio, TX.

      ). Using the standardized PHQ scoring mechanisms, major depression, panic syndrome, and other anxiety syndromes were assessed at baseline (
      • Spitzer R.L.
      • Kroenke K.
      • Williams J.B.
      Validation and utility of a self-report version of PRIME-MD: The PHQ Primary Care Study. Primary care evaluation of mental disorders.
      ,
      • Spitzer R.L.
      • Williams J.B.
      • Kroenke K.
      • Hornyak R.
      • McMurray J.
      Validity and utility of the PRIME-MD patient health questionnaire in assessment of 3000 obstetric-gynecologic patients: The PRIME-MD Patient Health Questionnaire Obstetrics-Gynecology Study.
      ,
      • Spitzer R.L.
      • Williams J.B.
      • Kroenke K.
      • Linzer M.
      • deGruy 3rd, F.V.
      • Hahn S.R.
      • et al.
      Utility of a new procedure for diagnosing mental disorders in primary care. The PRIME-MD 1000 study.
      ). Binge-like eating disorders were assessed applying criteria from the DSM-IV-TR to PHQ questions regarding eating behaviors. Participants were classified as having a mental disorder if they screened positive for one or more of the following conditions at baseline: PTSD, major depression, panic syndrome, other anxiety syndrome, or binge-like eating disorder.
      Because stressful life experiences, such as major financial problems or death of a family member, may be associated with sexual stressors, an aggregate variable was created to measure life stress before baseline (low, moderate, or severe life stress), which may have occurred before entering military service (
      • Holmes T.H.
      • Rahe R.H.
      The Social Readjustment Rating Scale.
      ).

      Demographics and Military Characteristics

      Demographic and military-specific data were obtained from Department of Defense electronic personnel files, including gender, birth date, highest education level, race/ethnicity, pay grade, service component (active duty and Reserve/National Guard), service branch (Army, Air Force, Navy/Coast Guard, and Marine Corps), and occupation. Marital status (single/widowed, married, separated/divorced before baseline, and separated/divorced since baseline) was based on self-report, with personnel data used to backfill missing information as necessary.
      Women who left military service between baseline and follow-up were classified as separated; all other women who were serving in the military from baseline to follow-up were classified as not separated.

      Statistical Analysis

      Descriptive and univariate analyses were conducted to compare demographic, military, and behavioral characteristics between the four sexual stressor categories. Multinomial logistic regression was used to ascertain independent associations between recent deployment experience and sexual stressors, after adjusting for demographics, military, and behavioral characteristics. Because it was plausible that prior sexual stressors might modify the relationship between recent deployment and recent sexual stressors, an interaction term was assessed. With the exception of basic demographics and the main exposures, variables that were not associated with the outcome (p > .10) and that did not confound the association of recent deployment experience with the outcome were removed from the final statistical model. Regression diagnostics were performed to assess collinearity among covariates, as well as goodness-of-fit tests. A subanalysis was conducted to examine the relationship between the five specific combat-like experiences and the sexual stressors. All data analyses were completed using SAS, version 9.2 (SAS Institute, Inc., Cary, NC). We obtained written consent from all participants.

      Results

      Of the 14,672 women who completed a baseline and first follow-up questionnaire, 816 who had separated from the military before baseline were excluded from the study. Of the 13,856 eligible participants, 524 did not complete the sexual stressor questions, 53 were missing the alcohol questions, 16 had missing demographic data, and 1 had missing combat experience data. Thus, the study population consisted of the remaining 13,262 women.
      Characteristics of the study sample are shown in Table 1. The study population consisted of women, among whom 92% were born before 1980, 43% had a high school education or less, 50% were married, 64% were White non-Hispanic, 73% were of enlisted pay grade, 50% were active duty members, 50% were in the Army, and 61% reported no previous sexual stressor.
      Table 1Characteristics of Millennium Cohort Female Participants by Sexual Stressors Report in the Past 3 Years
      Baseline Characteristics
      All variables, except race/ethnicity, service component, and separation from military, were significant at the p < .05 level.
      Study Sample (n = 1,262), %
      Percentages may not sum to 100 owing to rounding.
      No Sexual Stressor (n = 11,900), n (%)Sexual Harassment (n = 1,089), n (%)Sexual Assault (n = 121), n (%)Sexual Harassment and Assault, (n = 152), n (%)
      Recent deployment experience
      Deployment defined as at least ≥1 days in support of the operations in Iraq or Afghanistan between baseline and follow-up. Combat deployment defined as reporting personal exposures to ≥1 of the following: Witnessing death, physical abuse, dead and/or decomposing bodies, maimed soldiers or civilians, prisoners of war, or refugees.
       Nondeployed79.69,603 (80.7)764 (70.2)88 (72.7)103 (67.8)
       Deployed without combat11.41,358 (11.4)119 (10.9)17 (14.1)17 (11.2)
       Deployed with combat9.0939 (7.9)206 (18.9)16 (13.2)32 (21.1)
      Deployment experience before baseline
      Deployed to ≥1 of the following: (1) The 1991 Gulf War, (2) Bosnia, Kosovo, or Southwest Asia between 1998 and 2000, or (3) in support of the operations in Iraq and Afghanistan before baseline.
       No78.69,300 (78.2)877 (80.5)105 (86.8)135 (88.8)
       Yes21.52,600 (21.9)212 (19.5)16 (13.2)17 (11.2)
      Birth year
       Before 196021.62,681 (22.5)159 (14.6)9 (7.4)13 (8.6)
       1960–196936.34,425 (37.2)317 (29.1)26 (21.5)40 (26.3)
       1970–197934.63,989 (33.5)483 (44.4)59 (48.8)58 (38.2)
       1980 or later7.6805 (6.8)130 (11.9)27 (22.3)41 (27.0)
      Education
       High school or less43.24,950 (41.6)603 (55.4)73 (60.3)106 (69.7)
       Some college26.43,191 (26.8)246 (22.6)26 (21.5)31 (20.4)
       Bachelor's or higher30.43,759 (31.6)240 (22.0)22 (18.2)15 (9.9)
      Marital status
      Assessed separated/divorced status using baseline and follow-up data; other marital categories assessed at baseline.
       Single/widowed23.02,674 (22.5)282 (25.9)40 (33.1)49 (32.2)
       Married49.86,157 (51.7)381 (35.0)26 (21.5)34 (22.4)
       Separated/divorced before baseline12.41,459 (12.3)152 (14.0)8 (6.6)20 (13.2)
       Separated/divorced since baseline14.91,610 (13.5)274 (25.2)47 (38.8)49 (32.2)
      Race/ethnicity
       White non-Hispanic63.57,555 (63.5)692 (63.5)76 (62.8)103 (67.8)
       Black non-Hispanic20.12,401 (20.2)211 (19.4)27 (22.3)26 (17.1)
       Other16.41,944 (16.3)186 (17.1)18 (14.9)23 (15.1)
      Military pay grade
       Enlisted72.98,533 (71.7)886 (81.4)101 (83.5)141 (92.8)
       Officer27.23,367 (28.3)203 (18.6)20 (16.5)11 (7.2)
      Service component
       Reserve/National Guard49.85,934 (49.9)543 (49.9)52 (43.0)78 (51.3)
       Active duty50.25,966 (50.1)546 (50.1)69 (57.0)74 (48.7)
      Branch of service
       Army50.35,830 (49.0)688 (63.2)61 (50.4)95 (62.5)
       Air Force29.93,669 (30.8)229 (21.0)30 (24.8)32 (21.1)
       Navy/Coast Guard17.92,197 (18.5)138 (12.7)22 (18.2)16 (10.5)
       Marine Corps1.9204 (1.7)34 (3.1)8 (6.6)9 (5.9)
      Occupation
       Combat specialists6.6771 (6.5)83 (7.6)11 (9.1)3 (2.0)
       Health care specialists23.32,843 (23.9)200 (18.4)20 (16.5)26 (17.1)
       Functional support43.35,185 (43.6)456 (41.9)42 (34.7)62 (40.8)
       Other26.83,101 (26.1)350 (32.1)48 (39.7)61 (40.1)
      Separation from military
      Separated from the U.S. military service between baseline and follow-up.
       No88.610,565 (88.8)956 (87.8)105 (86.8)129 (84.9)
       Yes11.41,335 (11.2)133 (12.2)16 (13.2)23 (15.1)
      Alcohol-related problems
      Participants endorsed ≥1 of 5 alcohol-related problems in the last 12 months, such as driving a car after consuming several drinks.
       No92.211,055 (92.9)953 (87.5)104 (86.0)119 (78.3)
       Yes7.8845 (7.1)136 (12.5)17 (14.1)33 (21.7)
      Binge drinking and/or heavy weekly drinking
      Participants reported consuming >7 drinks per week, ≥4 drinks per day/occasion at baseline.
       No67.78,195 (68.9)635 (58.3)67 (55.4)85 (55.9)
       Yes32.33,705 (31.1)454 (41.7)54 (44.6)67 (44.1)
      Positive screen for mental disorder
      Participants screened positive at baseline for ≥1 of the following conditions: Posttraumatic stress disorder, depression, panic or other anxiety syndrome, or disordered eating.
       No89.610,770 (90.5)904 (83.0)96 (79.3)108 (71.1)
       Yes10.41,130 (9.5)185 (17.0)25 (20.7)44 (29.0)
      Life stress
      Using similar scoring mechanism introduced by Holmes and Rahe, life stress was based on reporting major financial problems, violent assault, severe illness or death of a family member or loved one, and disabling illness or injury at baseline.
       Mild95.811,464 (96.3)1,001 (91.9)109 (90.1)127 (83.6)
       Moderate/severe4.2436 (3.7)88 (8.1)12 (9.9)25 (16.5)
      Prior sexual stressors
      Participants who reported ever experiencing sexual harassment or sexual assault at baseline.
       No61.17,713 (64.8)314 (28.8)45 (37.2)35 (23.0)
       Yes38.94,187 (35.2)775 (71.2)76 (62.8)117 (77.0)
      All variables, except race/ethnicity, service component, and separation from military, were significant at the p < .05 level.
      Percentages may not sum to 100 owing to rounding.
      Deployment defined as at least ≥1 days in support of the operations in Iraq or Afghanistan between baseline and follow-up. Combat deployment defined as reporting personal exposures to ≥1 of the following: Witnessing death, physical abuse, dead and/or decomposing bodies, maimed soldiers or civilians, prisoners of war, or refugees.
      § Deployed to ≥1 of the following: (1) The 1991 Gulf War, (2) Bosnia, Kosovo, or Southwest Asia between 1998 and 2000, or (3) in support of the operations in Iraq and Afghanistan before baseline.
      Assessed separated/divorced status using baseline and follow-up data; other marital categories assessed at baseline.
      Separated from the U.S. military service between baseline and follow-up.
      # Participants endorsed ≥1 of 5 alcohol-related problems in the last 12 months, such as driving a car after consuming several drinks.
      ∗∗ Participants reported consuming >7 drinks per week, ≥4 drinks per day/occasion at baseline.
      †† Participants screened positive at baseline for ≥1 of the following conditions: Posttraumatic stress disorder, depression, panic or other anxiety syndrome, or disordered eating.
      ‡‡ Using similar scoring mechanism introduced by Holmes and Rahe, life stress was based on reporting major financial problems, violent assault, severe illness or death of a family member or loved one, and disabling illness or injury at baseline.
      §§ Participants who reported ever experiencing sexual harassment or sexual assault at baseline.
      Of the 13,262 participants, 1,362 (10.3%) reported at least one sexual stressor in the 3-year follow-up period (Table 1). Of those, 1,089 (80.0%) reported sexual harassment, 121 (8.9%) reported sexual assault, and 152 (11.2%) reported both sexual harassment and assault. Thus, the 3-year cumulative incidence of sexual harassment was 9.4% (n = 1,241) and sexual assault was 2.1% (n = 273).
      Approximately 20% of the women deployed between baseline and follow-up; of these, 1,193 (44.1%) reported combat-like experiences (Table 2). Women who were deployed who experienced combat reported the highest cumulative incidence of sexual harassment (19.9%) and sexual assault (4.0%) in the 3-year follow-up period.
      Table 2Three-Year Cumulative Incidence of Sexual Stressors among Female Participants by Recent Deployment Status
      Recent Deployment Status
      Deployment defined as at least ≥1 days in support of the operations in Iraq or Afghanistan between baseline and follow-up. Combat deployment defined as reporting personal exposures to ≥1 of the following: Witnessing death, physical abuse, dead and/or decomposing bodies, maimed soldiers or civilians, prisoners of war, or refugees.
      Study Sample (n = 13,262), nSexual Harassment (n = 1,241), n (%)Sexual Assault (n = 273), n (%)
      No deployment10,558867 (8.2)191 (1.8)
      Deployment without combat1,511136 (9.0)34 (2.3)
      Deployment with combat1,193238 (19.9)48 (4.0)
      Deployment defined as at least ≥1 days in support of the operations in Iraq or Afghanistan between baseline and follow-up. Combat deployment defined as reporting personal exposures to ≥1 of the following: Witnessing death, physical abuse, dead and/or decomposing bodies, maimed soldiers or civilians, prisoners of war, or refugees.
      The results from the final multinomial logistic regression, adjusting for demographics, pay grade, service branch, occupation, mental disorders, life stressors, and prior sexual stressors are shown in Table 3. Because prior sexual trauma did not modify the relationship (p = .89), no stratification was needed and prior sexual trauma was adjusted for in the final model. Combat deployment in support of the recent conflicts was significantly associated with sexual harassment (odds ratio [OR], 2.20, 95% confidence interval [CI], 1.84–2.64) and with both sexual harassment and sexual assault (OR, 2.47; 95% CI, 1.61–3.78), but not the sexual assault only category. Women who deployed before baseline had lower odds of sexual harassment and sexual assault (OR, 0.52; 95% CI, 0.31–0.89) compared with women who did not previously deploy.
      Table 3Adjusted Odds of Reporting Sexual Stressors Compared with Reporting of No Sexual Stressors among Female Millennium Cohort Participants (n = 13,262)
      Baseline CharacteristicsSexual Harassment (n = 1,089), AOR (95% CI)Sexual Assault (n = 121), AOR (95% CI)Sexual Harassment and Assault (n = 152), AOR (95% CI)
      Recent deployment
      Deployment defined as at least ≥1 days in support of the operations in Iraq or Afghanistan between baseline and follow-up. Combat deployment defined as reporting personal exposures to ≥1 of the following: Witnessing death, physical abuse, dead and/or decomposing bodies, maimed soldiers or civilians, prisoners of war, or refugees.
      experience
      Model adjusted for all variables in the table. Service component, separation from military, alcohol-related problems, and binge/heavy drinking were removed from the final model because they were not associated with the outcome and did not confound the association between deployment and sexual stressors.
       Nondeployed1.001.001.00
       Deployed without combat1.12 (0.91–1.39)1.16 (0.67–2.00)1.20 (0.70–2.06)
       Deployed with combat2.20 (1.84–2.64)
      Statistically significant.
      1.46 (0.84–2.55)2.47 (1.61–3.78)
      Statistically significant.
      Deployment experience before baseline
      Deployed to ≥1 of the following: (1) The 1991 Gulf War, (2) Bosnia, Kosovo, or Southwest Asia between 1998 and 2000, or (3) in support of the operations in Iraq and Afghanistan before baseline.
       No1.001.001.00
       Yes0.87 (0.74–1.03)0.60 (0.35–1.03)0.52 (0.31–0.89)
      Statistically significant.
      Birth year
       Before 19601.001.001.00
       1960–19691.10 (0.89–1.36)1.53 (0.70–3.34)1.63 (0.85–3.12)
       1970–19791.63 (1.32–2.01)
      Statistically significant.
      3.17 (1.49–6.76)
      Statistically significant.
      1.99 (1.03–3.85)
      Statistically significant.
       1980 or later1.95 (1.45–2.61)6.11 (2.55–14.65)5.33 (2.54–11.19)
      Statistically significant.
      Education
       High school or less1.001.001.00
       Some college0.95 (0.79–1.15)0.94 (0.54–1.64)0.82 (0.50–1.35)
       Bachelor's or higher0.97 (0.76–1.24)0.84 (0.38–1.88)0.66 (0.31–1.41)
      Marital status
      Assessed separated/divorced status using baseline and follow-up data; other marital categories assessed at baseline.
       Single/widowed1.001.001.00
       Married0.70 (0.59–0.83)
      Statistically significant.
      0.39 (0.23–0.65)0.42 (0.27–0.67)
       Separated/divorced before baseline1.17 (0.93–1.47)0.61 (0.27–1.35)1.05 (0.59–1.88)
       Separated/divorced since baseline1.54 (1.27–1.86)
      Statistically significant.
      2.06 (1.33–3.21)
      Statistically significant.
      1.54 (1.01–2.36)
      Statistically significant.
      Race/ethnicity
       White non-Hispanic1.001.001.00
       Black non-Hispanic0.93 (0.78–1.10)1.24 (0.78–1.98)0.78 (0.50–1.23)
       Other1.05 (0.88–1.27)0.99 (0.58–1.69)1.16 (0.72–1.86)
      Military pay grade
       Enlisted1.31 (1.02–1.68)
      Statistically significant.
      0.85 (0.38–1.89)1.95 (0.83–4.57)
       Officer1.001.001.00
      Branch of service
       Army1.57 (1.30–1.89)
      Statistically significant.
      0.92 (0.54–1.55)1.15 (0.71–1.87)
       Air Force1.001.001.00
       Navy/Coast Guard0.93 (0.73–1.19)1.03 (0.54–1.94)0.72 (0.37–1.41)
       Marine Corps2.03 (1.33–3.10)
      Statistically significant.
      2.93 (1.22–7.04)
      Statistically significant.
      3.03 (1.30–7.03)
      Statistically significant.
      Occupation
       Combat specialists1.43 (1.07–1.91)
      Statistically significant.
      1.48 (0.67–3.24)0.38 (0.11–1.29)
       Health care specialists1.001.001.00
       Functional support1.03 (0.85–1.24)0.90 (0.52–1.58)0.88 (0.54–1.43)
       Other1.18 (0.97–1.44)1.35 (0.78–2.35)1.16 (0.71–1.90)
      Positive screen for mental disorder
      Participants screened positive at baseline for ≥1 of the following conditions: Posttraumatic stress disorder, depression, panic or other anxiety syndrome, or disordered eating.
       No1.001.001.00
       Yes1.30 (1.09–1.56)1.58 (0.99–2.52)2.14 (1.47–3.13)
      Statistically significant.
      Life stress
      Using similar scoring mechanism introduced by Holmes and Rahe, life stress was based on reporting major financial problems, violent assault, severe illness or death of a family member or loved one, and disabling illness or injury at baseline.
       Mild1.001.001.00
       Moderate/severe1.40 (1.08–1.80)
      Statistically significant.
      2.44 (1.28–4.66)
      Statistically significant.
      2.95 (1.81–4.79)
      Statistically significant.
      Prior sexual stressors
      Participants who reported ever experiencing sexual harassment or sexual assault at baseline.
       No1.001.001.00
       Yes4.34 (3.77–5.00)
      Statistically significant.
      2.90 (1.97–4.25)
      Statistically significant.
      5.35 (3.61–7.93)
      Statistically significant.
      Abbreviations: AOR, adjusted odds ratio; CI, confidence interval.
      Deployment defined as at least ≥1 days in support of the operations in Iraq or Afghanistan between baseline and follow-up. Combat deployment defined as reporting personal exposures to ≥1 of the following: Witnessing death, physical abuse, dead and/or decomposing bodies, maimed soldiers or civilians, prisoners of war, or refugees.
      Model adjusted for all variables in the table. Service component, separation from military, alcohol-related problems, and binge/heavy drinking were removed from the final model because they were not associated with the outcome and did not confound the association between deployment and sexual stressors.
      Statistically significant.
      § Deployed to ≥1 of the following: (1) The 1991 Gulf War, (2) Bosnia, Kosovo, or Southwest Asia between 1998 and 2000, or (3) in support of the operations in Iraq and Afghanistan before baseline.
      Assessed separated/divorced status using baseline and follow-up data; other marital categories assessed at baseline.
      Participants screened positive at baseline for ≥1 of the following conditions: Posttraumatic stress disorder, depression, panic or other anxiety syndrome, or disordered eating.
      # Using similar scoring mechanism introduced by Holmes and Rahe, life stress was based on reporting major financial problems, violent assault, severe illness or death of a family member or loved one, and disabling illness or injury at baseline.
      ∗∗ Participants who reported ever experiencing sexual harassment or sexual assault at baseline.
      In addition, the youngest women, born in 1980 or later, were more than five times more likely to report sexual assault, with or without sexual harassment, than those born before 1960. Female service members who reported prior sexual stressors were nearly three times as likely to report recent sexual assault and more than four times as likely to report recent sexual harassment or both sexual stressors compared with those who did not report prior assault. Women serving in the Marine Corps were twice as likely to report sexual stressors, whereas women serving in the Army had a 57% increased odds for sexual harassment compared with Air Force service members. Other characteristics associated with sexual stressors at follow-up included marital status (separated or divorced since baseline), life stress, baseline mental disorders, occupation (combat specialists), and enlisted pay grade.
      The subanalysis examining the relationship between the specific combat-like experiences and sexual stressors revealed that each of the five items was significantly related to the sexual harassment outcome, but only “witnessing physical abuse” was significantly associated with the sexual assault outcome. This item was then removed from the definition of combat experience to test whether the association would remain significant in the primary model, and results were consistent.

      Discussion

      Over the past two decades, the role of women in the U.S. military has expanded, encompassing most occupations in the military to include combat support roles. Although much research has investigated the health of service members deployed in support of the operations in Iraq and Afghanistan, it has been challenging to address the experiences of female service members with regard to sexual stressors. This is among the first studies to investigate the association between recent deployment experiences and sexual stressors among U.S. military women.
      This study found that women who deployed to the current operations with combat-like experiences had significantly greater odds of reporting sexual harassment or both sexual harassment and assault, after adjustment. Women who experience combat while deployed are not only in more stressful and dangerous circumstances, but they may also find themselves in more traditionally male-dominated environments compared with other deployed women. Furthermore, in these high-stress and often life-threatening environments, prioritizing the identification and prevention of sexual stressors may be more challenging, perpetrators may be less concerned with the consequences of committing assault, and perpetrators may be less likely to be held accountable for their actions. Although this study could not determine the specific timing of the stressors, 70% of the women reported that the most recent sexual stressor occurred during a year coinciding with a time they were deployed. However, some combat-deployed women may be victims of sexual stressors either before or after deployment. Previous research indicates an association between combat experience and risky driving after deployment, so it is conceivable that women who experience combat may be more likely to engage in other risky behaviors when they return from deployment, which may increase their risk for sexual stressors (
      • Fear N.T.
      • Iversen A.C.
      • Chatterjee A.
      • Jones M.
      • Greenberg N.
      • Hull L.
      • et al.
      Risky driving among regular armed forces personnel from the United Kingdom.
      ).
      The findings from a subanalysis revealed that each of the five combat items (e.g., witnessing death, witnessing physical abuse) was significantly associated with recent sexual harassment. This may suggest that these experiences are coupled with violent environments where people are likely to aggress against military women.
      Interestingly, those who had deployed before baseline were at reduced odds of reporting recent sexual stressors; however, this association was only significant with regard to reporting both recent sexual stressors. Women who had previously deployed may have developed or enhanced coping skills that were helpful in avoiding future harassment and assault. Conversely, this finding may be a selection effect, in that female victims of unwanted sexual experiences may be more likely to leave the military (
      • Sadler A.G.
      • Booth B.M.
      • Cook B.L.
      • Torner J.C.
      • Doebbeling B.N.
      The military environment: risk factors for women's non-fatal assaults.
      ).
      Some of our findings regarding sociodemographics correspond with previous research, such as the increased risk of sexual stressors with younger age (
      • Coyle B.S.
      • Wolan D.L.
      • Van Horn A.S.
      The prevalence of physical and sexual abuse in women veterans seeking care at a Veterans Affairs Medical Center.
      ,
      • Street A.E.
      • Strafford J.
      • Mahan C.M.
      • Hendricks A.
      Sexual harassment and assault experienced by reservists during military service: Prevalence and health correlates.
      ). It was also expected that marriage would be a protective factor. Those recently separated or divorced were at increased risk, but no increased risk was seen among those separated or divorced before baseline. It is possible that women who separated or divorced before baseline had more time to develop effective ways of coping with or avoiding situations that increase the likelihood of harassment or assault.
      Consistent with previous research, this study found a strong association between prior sexual stressors and recent sexual stressors. Prevailing opinion suggests that the mechanisms explaining this association are complex and need to encompass consideration not just of the victim but also of the aggressor (
      • Elwood L.S.
      • Smith D.W.
      • Resnick H.S.
      • Gudmundsdottir B.
      • Amstadter A.B.
      • Hanson R.F.
      • et al.
      Predictors of rape: findings from the National Survey of Adolescents.
      ,
      • Kapur N.A.
      • Windish D.M.
      Health care utilization and unhealthy behaviors among victims of sexual assault in Connecticut: Results from a population-based sample.
      ,
      • Lalor K.
      • McElvaney R.
      Child sexual abuse, links to later sexual exploitation/high-risk sexual behavior, and prevention/treatment programs.
      ,
      • Mosack K.E.
      • Randolph M.E.
      • Dickson-Gomez J.
      • Abbott M.
      • Smith E.
      • Weeks M.R.
      Sexual risk-taking among high-risk urban women with and without histories of childhood sexual abuse: mediating effects of contextual factors.
      ). Socialization, health, culture, religion, economics, and psychological processes all may play roles in explaining this association (
      • Sadler A.G.
      • Booth B.M.
      • Mengeling M.A.
      • Doebbeling B.N.
      Life span and repeated violence against women during military service: effects on health status and outpatient utilization.
      ). In addition, a strong association between previous life stressors and sexual stressors was found. Further analysis showed that although each component of the life stressors metric was associated with sexual stressors, history of violent assault was most influential in this relationship. These results are similar to other work indicating an association between physical assault and sexual assault (
      • Busch-Armendariz N.B.
      • DiNitto D.M.
      • Bell H.
      • Bohman T.
      Sexual assault perpetrators' alcohol and drug use: the likelihood of concurrent violence and post-sexual assault outcomes for women victims.
      ,
      • Mohammadkhani P.
      • Forouzan A.S.
      • Khooshabi K.S.
      • Assari S.
      • Lankarani M.M.
      Are the predictors of sexual violence the same as those of nonsexual violence? A gender analysis.
      ).
      Previous research has documented an association between mental disorders and sexual stressors in military populations, which is similar to the association we found (
      • Kimerling R.
      • Gima K.
      • Smith M.W.
      • Street A.
      • Frayne S.
      The Veterans Health Administration and military sexual trauma.
      ,
      • Murdoch M.
      • Pryor J.B.
      • Polusny M.A.
      • Gackstetter G.D.
      Functioning and psychiatric symptoms among military men and women exposed to sexual stressors.
      ). Because of the cross-sectional design of previous studies, however, it has not been fully established whether prior mental health morbidity increases the risk for experiencing these stressors. Our findings found that those who screened positive for a mental disorder at baseline, such as PTSD or depression, were at an increased risk for experiencing sexual stressors. These women may be more vulnerable because of their mental status and/or perpetrators may be more likely to aggress against women with these conditions.
      Consistent with a previous report (
      • Lipari R.N.
      • Lancaster A.R.
      Armed forces 2002 sexual harassment survey.
      ), enlisted women, combat specialists, and Army soldiers had significantly increased odds of reporting sexual harassment; female Marines were significantly more likely to report all sexual stressors. The increased risk of sexual stressors among Marines, soldiers, and combat specialists may be related to these women being embedded in environments with a higher proportion of men. This may create a more masculine-oriented environment, which perhaps facilitates sexual stressor events. That is, this type of environment may decrease the willingness of women to report incidents of sexual stressors to military commanders; therefore, the leaders may believe that sexual stressors are not prevalent and that additional efforts to prevent these stressors are unnecessary. In addition, perpetrators may believe that there are few or no consequences for their actions.
      The percentage of deployers reporting sexual harassment in a 3-year follow-up period for this study (9% without combat experience and 20% with combat experience) was lower than prior studies of female service members. For example, rates of sexual harassment over a 1-year period were found to be between 24% and 66% among women who deployed to the 1991 Gulf War (
      • Carney C.P.
      • Sampson T.R.
      • Voelker M.
      • Woolson R.
      • Thorne P.
      • Doebbeling B.N.
      Women in the Gulf War: combat experience, exposures, and subsequent health care use.
      ,
      • Kang H.
      • Dalager N.
      • Mahan C.
      • Ishii E.
      The role of sexual assault on the risk of PTSD among Gulf War veterans.
      ,
      • Wolfe J.
      • Sharkansky E.
      • Read J.
      • Dawson R.
      • Martin J.
      • Ouimette P.
      Sexual harassment and assault as predictors of PTSD symptomatology among US female Persian Gulf War military personnel.
      ) and 24% to 34% among women serving in the Armed Forces (
      • Lipari R.N.
      • Cook P.J.
      • Rock L.M.
      • Matos K.
      2006 Gender relations survey of active duty members.
      ,
      • Lipari R.N.
      • Lancaster A.R.
      Armed forces 2002 sexual harassment survey.
      ). Rates in this current study are lower than that reported for U.S. civilian women, although accurate estimates for the latter are difficult to obtain (
      • Charney D.A.
      • Russell R.C.
      An overview of sexual harassment.
      ). However, this study only used one question to assess sexual harassment, whereas many previous studies have used multi-item survey instruments, which tends to increase case finding (
      • Fisher B.
      • Cullen F.
      ).
      The percentage of women reporting sexual assault in a 3-year period in this study (3% among deployed) was comparable to a nationally representative sample of women who deployed to the 1991 Gulf War (
      • Kang H.
      • Dalager N.
      • Mahan C.
      • Ishii E.
      The role of sexual assault on the risk of PTSD among Gulf War veterans.
      ). For nondeployed service women, recent estimates of sexual assault over a 1-year time frame have ranged from 2% to 5% in nationally representative and subsamples of female service members (
      • Bostock D.J.
      • Daley J.G.
      Lifetime and current sexual assault and harassment victimization rates of active-duty United States Air Force women.
      ,
      • Cunradi C.
      • Ames G.
      • Moore R.
      Prevalence and correlates of interpersonal violence victimization in a junior enlisted Navy cohort.
      ,
      • Lipari R.N.
      • Cook P.J.
      • Rock L.M.
      • Matos K.
      2006 Gender relations survey of active duty members.
      ,
      • Lipari R.N.
      • Lancaster A.R.
      Armed forces 2002 sexual harassment survey.
      ).

      Strengths and Limitations

      This is the first study to analyze the association between deployment in support of the operations in Iraq and Afghanistan and sexual stressors in a large, population-based cohort of military women, including those who serve in the Reserves and National Guard. Numerous investigations for potential biases have found the Millennium Cohort to be representative of military personnel and suggest data reporting is reliable with minimal non-response bias (
      • Chretien J.P.
      • Chu L.K.
      • Smith T.C.
      • Smith B.
      • Ryan M.A.
      Demographic and occupational predictors of early response to a mailed invitation to enroll in a longitudinal health study.
      ,
      • LeardMann C.A.
      • Smith B.
      • Smith T.C.
      • Wells T.S.
      • Ryan M.A.
      Smallpox vaccination: Comparison of self-reported and electronic vaccine records in the Millennium Cohort Study.
      ,
      • Riddle J.R.
      • Smith T.C.
      • Smith B.
      • Corbeil T.E.
      • Engel C.C.
      • Wells T.S.
      • et al.
      Millennium Cohort: The 2001-2003 baseline prevalence of mental disorders in the U.S. military.
      ,
      • Ryan M.A.
      • Smith T.C.
      • Smith B.
      • Amoroso P.
      • Boyko E.J.
      • Gray G.C.
      • et al.
      Millennium Cohort: Enrollment begins a 21-year contribution to understanding the impact of military service.
      ,
      • Smith T.C.
      • Zamorski M.
      • Smith B.
      • Riddle J.R.
      • LeardMann C.A.
      • Wells T.S.
      • et al.
      The physical and mental health of a large military cohort: Baseline functional health status of the Millennium Cohort.
      ,
      • Smith B.
      • Leard C.A.
      • Smith T.C.
      • Reed R.J.
      • Ryan M.A.
      Anthrax vaccination in the Millennium Cohort: validation and measures of health.
      ,
      • Smith T.C.
      • Jacobson I.G.
      • Smith B.
      • Hooper T.I.
      • Ryan M.A.
      The occupational role of women in military service: Validation of occupation and prevalence of exposures in the Millennium Cohort Study.
      ,
      • Smith B.
      • Wingard D.L.
      • Ryan M.A.K.
      • Macera C.A.
      • Patterson T.L.
      • Slymen D.J.
      US military deployment during 2001-2006: Comparison of subjective and objective data sources in a large prospective health study.
      ,
      • Wells T.S.
      • Jacobson I.G.
      • Smith T.C.
      • Spooner C.N.
      • Smith B.
      • Reed R.J.
      • et al.
      Prior health care utilization as a potential determinant of enrollment in a 21-year prospective study, the Millennium Cohort Study.
      ). Recall errors may also have been reduced, since outcome information was collected within a relatively short period (3 years) of the event(s). Furthermore, information regarding individual vulnerability factors was collected before measuring the outcome, avoiding the problems of retrospective recall that can bias results when information about outcomes and risk factors are collected simultaneously. This study also addressed potential confounding by prior sexual stressor experiences by controlling for such history in our analyses. Although we relied on self-reported symptoms and not a clinical assessment, the PCL-C and PHQ may have actually more accurately capture those with mental health symptoms than actual clinical diagnoses or hospitalization data, because many individuals with mental health disorders do not seek treatment (
      • Hoge C.W.
      • Castro C.A.
      • Messer S.C.
      • McGurk D.
      • Cotting D.I.
      • Koffman R.L.
      Combat duty in Iraq and Afghanistan, mental health problems, and barriers to care.
      ).
      This study also had several limitations. The sexual stressor questions on the Millennium Cohort questionnaires capture events that have occurred during the 3-year follow-up period, so it was not possible to ascertain whether these events occurred before, during, or after deployments. However, 70% of women reported the most recent sexual stressor event happening during the year they were deployed. In addition, no information was collected on the perpetrators, so we were not able to identify or characterize these individuals. Although unlikely, we cannot eliminate the possibility that the association found between combat deployment and sexual stressors could be related to reporting error, in that women who report combat experience may also be more likely to report sexual stressors. Because abbreviated measures that lack detailed descriptions or definitions were used to assess sexual stressors, and because unwanted sexual experiences may carry a stigma, participants may under- or over-report traumatic events; further, recall of traumatic events may be imperfect and influenced by the assessment process itself (
      • Krinsley K.E.
      • Gallagher J.G.
      • Weathers F.W.
      • Kutter C.J.
      • Kaloupek D.G.
      Consistency of retrospective reporting about exposure to traumatic events.
      ). Although the combat-like experiences were reported to have occurred during a time coinciding with deployment, the questions are not specific to deployment; therefore, it is possible that these events did not occur during deployment. Last, the PCL-C and PHQ were used to assess mental disorders, and although they are standardized and validated instruments, they cannot stand in for a clinical diagnosis and thus, may misclassify mental health status.

      Implications for Practice and Policy

      Understanding the factors that contribute to sexual stressors is the first step in designing and evaluating interventions aimed at reducing these stressors in the military. Our findings indicate that some of the risk factors for sexual stressors are related to the type of environment (e.g., combat experience, branch of service), whereas others are related to individual risk and resiliency factors (e.g., age, marital status, mental health conditions). In designing and testing interventions to prevent sexual stressors, it may be practical to target these environments, as well as focus on enhancing resiliency factors in younger women, those newly separated or divorced, and those with positive mental health screens. Sexual stressors are not unique to the military. Challenges have been well-described among young women in university and occupational settings (
      • Brown L.P.
      • Rospenda K.M.
      • Sokas R.K.
      • Conroy L.
      • Freels S.
      • Swanson N.G.
      Evaluating the association of workplace psychosocial stressors with occupational injury, illness, and assault. [Research Support, N.I.H., Extramural Research Support, U.S. Gov't, P.H.S.].
      ,
      • Connor J.
      • Gray A.
      • Kypri K.
      Drinking history, current drinking and problematic sexual experiences among university students.
      ). Military occupations, however, clearly provide a complicated and unique set of stressors when operational deployments are considered. The recent change to open positions to women whose primary mission is to engage in direct combat is likely to increase the numbers of women serving in combat roles and those deployed with combat (
      • U.S. Department of Defense and Joint Chiefs of Staff
      Elimination of the 1994 Direct Ground Combat Definition and Assignment Rule. 24 Jan 2013.
      ). Therefore, it is critical, now more than ever, to evaluate ways to prevent and eliminate sexual stressors in these environments that are associated with increased risk of sexual stressors. Programs to prevent sexual harassment and assault in civilian communities have resulted in minimal or mixed success (
      • Vladutiu C.J.
      • Martin S.L.
      • Macy R.J.
      College- or university-based sexual assault prevention programs: A review of program outcomes, characteristics, and recommendations.
      ), and the military has recognized that a sustained effort to eliminate sexual stressors is necessary. The U.S. Department of Defense has developed programs in recent years, with mandatory training at all levels that also use social media tools to prevent sexual assault against both female and male service members, yet more steps need to be taken to mitigate sexual stressors in the military (
      • U.S. Department of Defense
      DoD Instruction 6495.02 Sexual Assault Prevention and Response Program Procedures, updated 13 Nov 2008.
      ,
      • U.S. Department of Defense
      Sexual Assault Prevention and Response: Fiscal Year 2009 Annual Report on Sexual Assault in the Military, March 2010.
      ). Because increased formal reporting of sexual stressors is one measure of programmatic success, public health policymakers will be challenged to measure actual effectiveness of programs in reducing sexual harassment or assault. Through continued assessments and studies, such as the Millennium Cohort, prospective collection of self-reported information on sexual stressors is essential for continued focus and measuring progress.

      Acknowledgments

      This work represents Naval Health Research Center report 11-53, supported by the U.S. Department of Defense , under work unit no. 60002, and funded by the Military Operational Medicine Research Program of the U.S. Army Medical Research and Materiel Command, Fort Detrick, Maryland. The views expressed in this article are those of the authors and do not reflect the official policy or position of the U.S. Department of the Navy, U.S. Department of the Army, U.S. Department of the Air Force, U.S. Department of Defense, U.S. Department of Veterans Affairs, nor the U.S. Government. The funding organizations had no role in the design and conduct of the study; collection, analysis, or preparation of data; or preparation, review, or approval of the manuscript.

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      Biography

      Cynthia A. LeardMann, MPH, is a Senior Epidemiologist for the Deployment Health Research Department at the Naval Health Research Center. Her research areas focus on mental health and women's health in military populations.
      Amanda Pietrucha, MPH, is a Data Analyst for the Deployment Health Research Department at the Naval Health Research Center.
      Kathryn M. Magruder, MPH, PhD, is a Research Health Scientist with the VA Medical Center and is a Professor of Psychiatry (Military Science Division) and Public Health Sciences (Epidemiology Division) at the Medical University of South Carolina, Charleston SC. Her research interests are in psychiatric epidemiology and PTSD.
      Besa Smith, MPH, PhD, is an Assistant Adjunct Professor in the Department of Family and Preventive Medicine, University of California, San Diego. Her research interests include tobacco, women's health, and military and veteran health.
      Dr. Maureen Murdoch, MD, MPH, is Core Investigator for the Minneapolis VA Health Services Research and Development Service Center of Excellence, the Center for Chronic Disease Outcomes Research; Staff Physician in the Section of General Internal Medicine, Minneapolis VA Health Care System; and Associate Professor of Medicine, University of Minnesota Medical School.
      Isabel G. Jacobson, MPH, is a Senior Epidemiologist for the Deployment Health Research Department at the Naval Health Research Center in San Diego, California. Her research interests include alcohol misuse and obesity.
      Margaret A.K. Ryan, MD, MPH, is a physician specializing in occupational and preventive medicine. She is currently the Head of the Clinical Investigation Program at Naval Hospital Camp Pendleton and she is an Adjunct Associate Professor in the Department of Family and Preventive Medicine at the University of California San Diego.
      Gary D. Gackstetter, DVM, MPH, PhD, is currently a Corporate Fellow, Analytic Services, Inc., Falls Church, Virginia, and formerly an Air Force Public Health Officer. He also, remains affiliated with Uniformed Services University of the Health Sciences as an Adjunct Associate Professor in the Department of Preventive Medicine and Biometrics. His research interests include military force health protection and illnesses among Gulf War veterans.
      Tyler C. Smith, MS, PhD, is an Associate Professor in the Department of Community Health, School of Health and Human Services, National University. His research interests include health analytics and informatics solutions, occupational epidemiology, veteran's health, behavioral health, and chronic disease epidemiology.