Health-Promoting Leadership during an Infectious Disease Outbreak: A Cross-sectional Study of US Soldiers Deployed to Liberia

Infectious disease outbreaks are uniquely stressful for non-medical essential employees. Promoting the health of these workers is vital to minimize their distress and to ensure they are able to continue in their professional capacity. One way to support worker health is for supervisors to engage in behaviors that promote their employees’ behavioral health, wellbeing, and attitudes towards preventive medicine practices. The present study examined if health-promoting leadership contributes to these outcomes in employees operating in an epidemic. Active-duty soldiers (N = 173) deployed to provide non-medical support in Liberia during the 2014 Ebola crisis completed surveys assessing posttraumatic stress disorder (PTSD), depression, anxiety, sleep problems, burnout, morale and attitudes, and rating their leaders on health-promoting behaviors. An exploratory factor analysis identied two leadership factors, one focused on psychological health and one on preventive medicine behaviors.

Moreover, there is some evidence that non-medical experts, such as clinical sanitation staff (3), also report anxiety and other behavioral health concerns. However, the degree to which the behavioral health of these non-medical groups is impacted by having to operate within the context of an infectious disease outbreak is less clear. Likewise, employees such as public transportation and delivery workers may be asked to function outside of the scope of their regular responsibilities. In their new roles, they may experience pressure to adapt to new unexpected demands in a setting where mistakes in following preventive measures have high-stakes consequences. Thus, it is important to understand the impact of these demands on employee behavioral health and what mitigates these effects.
One opportunity to understand this dynamic is the deployment of non-medical US Army units to Liberia in response to the Ebola outbreak of 2014. These soldiers were deployed as part of Operation United Assistance in which 3,000 service members built laboratories and Ebola treatment units, disseminated knowledge to local nationals on personal protective equipment, and provided logistical and security support (15,16). In a survey conducted with these deployed soldiers, Sipos et al. (16) reported the range of stressors, behavioral health concerns, and attitudes toward the deployment. These attitudes included knowledge of preventive medicine measures and positive attitudes toward the deployment. Combined, these positive attitudes were inversely correlated with stressors and behavioral health. These data also offer an opportunity to examine factors that may mitigate the impact of stressors on behavioral health, burnout, sleep, morale and positive attitudes in personnel tasked with operating in high-stakes environments.
Indeed, infection is a real risk facing personnel responsible for responding to a disease outbreak. Engaging in preventive medicine practices at the individual and organizational level addresses risk. While organizations, including the military, can institute these practices, they rely on personnel to adopt them. Attitude is a core construct that drives intention according to the Theory of Planned Behavior(31) which has successfully predicted health behaviors such as physical activity and diet (32), hand washing (33), and wearing gloves (34). Thus, attitudes about disease risk and preventive medicine measures may signal the willingness of personnel to comply with preventive medicine practices.
Given the stressors encountered by non-medical employees and the need to ensure that they follow preventive medicine practices, it is important to examine what in uences employee adaptation during an epidemic. In a high-risk occupational context like the military, leadership is one key mitigating factor.
Numerous studies have documented the role of leaders in in uencing behavioral health and attitudes of military personnel (35)(36)(37).
While leadership in general is associated with better outcomes for military units, emerging research highlights the potential utility of focusing on speci c leadership behaviors targeting speci c domains. Domain-speci c leadership has been studied in a variety of contexts from family-supportive supervisory behaviors (38) to safety leadership (39,40). In the military, this concept has included combat operational stress control leadership (41), sleep leadership (42,43), and health-promoting leadership (41,44,45). This research identi es speci c areas that leaders can focus on to support relevant outcomes. Healthpromoting leadership may offer an important perspective on behaviors that are associated with healthrelated outcomes during an infectious disease outbreak.
Health-promoting leadership is de ned as the set of leader behaviors intended to support the maintenance of team member psychological and physical health and wellbeing while ful lling professional responsibilities. This construct has been associated with decreased burnout symptoms, speci cally exhaustion and depersonalization among medical staff deployed to Afghanistan (44). It was also associated with fewer depression and anxiety symptoms, more positive attitudes toward the mission, and more positive attitudes toward preventive medicine measures in soldiers quarantined for 21 days following deployment to Liberia, even after controlling for general leadership (45). Health-promoting leadership has also been associated with better mental health and positive attitudes for soldiers in quarantine following deployment over and above general leadership (45).
While these studies demonstrate that health-promoting leadership may be useful, there are several key remaining questions that address the utility of this construct in an applied setting. First, it is not clear whether health-promoting leadership is a single construct or composed of multiple factors. Second, it is not known whether health-promoting leadership is related to better outcomes during a mission in which units have to perform their tasks while confronted with the profound threat of infectious disease. Finally, while the relationship between health-promoting leadership and behavioral health (41), and attitudes toward quarantine (45) has been established, it is unknown whether these same leadership behaviors are associated with morale and attitudes toward disease risk and preventive medicine practices, over and above the role of general leadership. Addressing these questions can inform the development of leadership training to optimize the development of speci c leadership strategies. Thus, the present study aims to examine the components of health-promoting leadership and identify which factors are associated with better behavioral health, wellbeing (de ned in this study as sleep, burnout and morale), and attitudes toward disease risk and preventive medicine practices in a sample of soldiers deployed to Liberia during the Ebola outbreak.

Study Design
As part of a study to determine key psychological stressors associated with deployment in support of a medical mission, soldiers completed anonymous and cross-sectional paper surveys (16). Study participants were all active duty soldiers supporting the U.S. response to the Ebola crisis in mainly non- and gender (male, female). Background information about deployment included months on current deployment (ranged from less than one month to ve months or more) and job category (medical, logistics, aviation, command and control, support, security/force protection, and other).

Health-Promoting Leadership
Health-promoting leadership measured soldiers' perceptions of leader behaviors focused on the preventive medicine goals of the mission as well as overall psychological health. This scale has been used in previous research with military units (44). Individual items are described in Table 2. Study participants were asked to rate their current team/unit leadership on 13 items in terms of how frequently they occurred (1 = never to 5 = always). Mean response scores for each of the 13 items were calculated. Cronbach's alpha for this scale was 0.96.

General Leadership
Soldiers' perceptions of general leadership behaviors were assessed using the four-item Walter Reed Army Institute of Research Leadership Scale (WRAIR-LS)-Short Form, a scale frequently used in research with military units (35,41,46). A sample item includes, "leader tells soldiers they have done a good job," and response options ranging from 1 = never to 5 = always. Negative items were reverse scored. Response scores were averaged. Internal consistency was 0.82.

Behavioral Health and Wellbeing
An adapted form of the 17-item posttraumatic stress disorder (PTSD) Checklist-Speci c assessed PTSD symptoms (47,48). The scale was dichotomized using a diagnostic algorithm for each cluster and overall score of 50 as the cutoff, which is consistent with other studies conducted with military populations (49). Internal consistency was 0.94.
The eight-item version of the Patient Health Questionnaire for Depression (PHQ-8) assessed depression symptoms of study participants (50). Items in the PHQ-8 are scored with four response options (0 = not at all to 3 = nearly every day). Items were summed, which resulted in a composite score ranging from 0 to 24. Respondents were indicated as a positive screen for depression if a summary score of 10 or more was met (51). Internal consistency was 0.90.
The seven-item Generalized Anxiety Disorder scale (GAD-7) assessed anxiety symptoms (52). Items were scored with four response options (0 = not at all to 3 = nearly every day). The seven items were summed, resulting in a composite score ranging from 0 to 21. Respondents were indicated as a positive score for anxiety if a summary score of 10 or more was met (53). Internal consistency was 0.92.
Sleep problems were measured using the seven-item Insomnia Severity Index (54). Items measured participants' di culty falling asleep, staying asleep, and problems waking up too early, in addition to their satisfaction and distress regarding sleep problems. Each item was scored on a scale ranging from 0 to 4.
A single item measured morale. The item asked participants to rate their personal morale from on a scale from 1 = very low to 5 = very high. Morale was dichotomized so that a response of three or below was considered low morale and a score of four or above was considered high morale.

Attitudes toward Disease Risk and Preventive Medicine Practices
Three items ("I understand the level of risk from disease"; "I know what to do to protect myself from disease"; "this deployment will make a meaningful difference in ghting the Ebola epidemic") adapted from Castro (55) and Sipos(56) were selected to assess attitudes towards the deployment. Items were rated on a ve-point scale from 1 = strongly disagree to 5 = strongly agree. The items were further dichotomized so that a score of four or higher was indicated as agreement.
A three-item scale developed for this study examined attitudes towards preventive medicine measures during deployment. Response questions included both positive ("taking our temperature twice a day makes sense to me") and negative ("taking our temperature twice a day is a waste of time"; "preventive medicine measures recommended for this deployment are not practical") items with response options ranging from 1 = strongly disagree to 5 = strongly agree. A positive score was indicated by a response of four or higher for the rst item, and a score of two or lower for the two negative items. Internal consistency was 0.73.
A single item developed for this study ("I avoided unnecessary risks on this mission") assessed preventive behaviors during deployment. Response options ranged from 1 = strongly disagree to 5 = strongly agree, and were dichotomized so that a score of four or higher was indicated as agreement.

Analysis
An exploratory factor analysis (extraction method: principal factor; rotation method: oblique promax with Kaiser normalization) of the health-promoting leadership scale was conducted. Two subscales were discovered: psychological health-promoting leadership and preventive medicine health-promoting leadership. Rotated factor loadings for each scale item are reported in Table 2. Internal consistency was 0.96 and 0.92 for the two factors, respectively.
The study aimed to examine the association between health-promoting leadership and behavioral health, attitudes, and behaviors of soldiers. The sample population is inherently hierarchical due to clustering effects by organizational unit, and therefore, assumptions of independence could not be met (57). Indeed, the main exposure of interest, health-promoting leadership, introduces non-independence, as clusters of participants in our sample had the same leaders. In order to account for non-independence, mixed effects logistic regression models were used to indicate associations between health-promoting leadership behaviors and outcomes of interest. Military units (companies nested within battalions) were modeled as the random intercepts. All models were adjusted for rank (junior enlisted, NCOs, and O cer/Warrant O cer) and general leadership (continuous). Other demographic and background covariates were tested for inclusion in the model but did not meet the criteria for confounding (i.e., associated with the exposure and outcome, change in odds ratios by > 10%). Listwise deletion was used to handle any missing data. All data analyses were conducted using STATA 14.

Results
Demographic and background data are shown in Table 1. Nearly all participants received training about infectious disease (99%), managing medical threats other than infectious disease (99%), managing emotional stress of deployment (96%), and cultural awareness (95%). Only 16% of respondents reported that they have experienced dealing with infectious disease threats on other missions.
Participants were asked to rank their current unit leaders on various behaviors. Health-promoting leadership items are displayed in Table 2. When examining health-promoting leadership as two separate factors, soldiers rated preventive medicine health-promoting leadership (M = 3.79, SD = 0.97) signi cantly higher than psychological health-promoting leadership (M = 3.28, SD = 1.06; t(169) = 8.68, p < .001).
Adjusted odds ratios (AORs) reporting the association between overall health-promoting leadership and measures of behavioral health, wellbeing and attitudes are displayed in Table 3. Overall, soldiers who rated health-promoting leadership higher had signi cantly reduced odds of PTSD, depression, anxiety, and high burnout, whereas health-promoting leadership increased the odds of high morale. Additionally, higher ratings of health-promoting leadership were associated with increased odds of both believing the deployment will make a meaningful difference in ghting the Ebola epidemic and avoiding unnecessary risks.
Results from the two health-promoting leadership factors are presented in Table 3. Increases in psychological health-promoting leadership ratings were associated with reduced odds of PTSD, depression and anxiety, and high burnout, as well as increased odds of high morale and avoiding unnecessary risks. Likewise, preventive medicine health-promoting leadership was associated with increased odds of high morale, and reduced odds of depression and anxiety, though the AORs were attenuated relative to psychological health-promoting leadership. In addition, increased ratings of preventive medicine health-promoting leadership was associated with increased odds of understanding the level of risk from disease, positive attitudes towards deployment making a meaningful difference, avoiding unnecessary risks, and positive attitudes towards preventive practices. Sleep problems and knowing how to protect oneself from disease were not associated with any health-promoting leadership behaviors.

Discussion
Working within an environment characterized by the threat of infectious disease can expose employees outside of the medical community to unusual occupational stressors, including the risk of infection. Thus, understanding how to help these employees function is essential given that they are expected to continue performing their jobs. The present study analyzed data from a survey of non-medical soldiers deployed to Liberia in response to an Ebola outbreak. Results documented that ratings of healthpromoting leadership were associated with positive soldier behavioral health, wellbeing, and morale, even after controlling for general leadership. Such results are consistent with existing literature indicating that speci c leader behaviors are associated with behavioral health and wellbeing outcomes (41,44) and positive attitudes toward quarantine (45).
Results identi ed two health-promoting leadership factors. These factors differentially predicted study metrics, underscoring the need to consider speci c leader behaviors when targeting speci c employee outcomes. One health-promoting leadership factor focused on psychological health. This factor was associated with lower odds of soldiers reporting PTSD, depression, anxiety and burnout. These leadership behaviors were also associated with higher levels of morale and avoiding unnecessary risks. This nding suggests that leaders who encourage self-care and support team goals have soldiers with fewer behavioral health di culties. In contrast, the other health-promoting leadership factor focused on preventive medicine. This factor was associated with lower odds of depression and anxiety, and higher odds of morale, avoiding unnecessary risks and positive attitudes toward preventive medicine practices. This nding suggests that leaders who emphasize the importance of these measures and lead by example are more likely to have soldiers who follow these practices and feel positively about them.
These ndings are consistent with research documenting the importance of perceived control in reducing stress (58) and increasing emotional wellbeing (59). They also suggest that leaders who focus on actions soldiers can take to reduce risk of infection may help reduce depression and anxiety as well. While both factors were associated with behavioral health measures, the factor focused on preventive medicine was more clearly linked with attitudes toward preventive medicine practices, suggesting that targeting speci c leadership behaviors aimed at emphasizing preventive medicine practices may increase occupational safety among those responding to infectious disease outbreaks.
Interestingly, neither the overall health-promoting leadership scale nor the factors were associated with reports of sleep problems. This is consistent with ndings from a study of soldiers in quarantine in which health-promoting leadership behaviors were not associated with insomnia (45). In contrast, studies examining sleep leadership have demonstrated links to sleep outcomes in military units (60). The current study's distinctive pattern of results further demonstrates the need to address leadership behaviors by focusing on domain-speci c topics.
Another outcome which was not associated with health-promoting leadership behaviors was "knowing how to protect oneself from disease." While this result was unexpected given that one factor speci cally emphasized preventive health, more than 90% of soldiers were con dent in their knowledge of how to protect themselves. Thus, a ceiling effect may have prevented this particular item from being signi cantly predicted by leadership behaviors.
While there are strengths of the current study, including the unusual sample and identi cation of speci c leader behaviors, there are limitations that must be taken into account. First, ndings are based on selfreported data; although studies have shown that anonymous self-reported measures can be a valid indicator of mental health and attitudes among this population (61). Second, the data are cross sectional and cannot address questions of causality, although the fact that general leadership served as a control variable helps strengthen con dence in the observed associations. Third, the study sample may have reduced the power to observe effects of leadership behavior, although several signi cant associations were identi ed.
Despite these limitations, these ndings offer direction for practical application such as leadership training programs. Although the study focused on the Ebola epidemic, the ndings may be relevant to other epidemics, including the COVID-19 pandemic, by offering insight into how leaders can effectively support personnel in non-medical positions. For example, as of June 2020, more than 62,000 service members have responded to the COVID-19 pandemic, only 3,500 of these personnel are medical (62). This demonstrates that behavioral health, wellbeing, and attitudes in service members are relevant not only for medical personnel but for non-medical support when operating within an infectious disease context. Future research should assess the degree to which health-promoting leadership is related to employee outcomes in non-military settings given the unique nature of military culture (63,64).

Conclusions
The COVID-19 pandemic has drawn attention to the vulnerability of essential workers such as supermarket cashiers, bus drivers, and custodial staff who provide vital support for their communities while confronting the threat of infectious disease. This increased risk may be outside the employee's typical scope of work, thus elevating the likelihood of behavioral health and wellbeing di culties. Besides providing measures such as personal protective equipment, physical distancing, and hygiene resources, it may be useful for leaders to consider engaging in speci c behaviors that support their employees during these di cult times. Such behaviors can be integrated into management training and company culture.
Indeed, results from the present study demonstrate that health-promoting behaviors are within the repertoire of supervisor actions given that many soldiers identi ed their leaders as frequently engaging in these behaviors. Still, approximately one in three soldiers reported that their leaders did not frequently engage in health-promoting behaviors, including encouraging preventive medicine practices, this suggests opportunities for improvement. Future research should examine the degree to which such these behaviors can be easily trained and encouraged in front-line supervisors, modeled on other domainspeci c leadership training (60,65). Future research should build on the health-promoting leadership behaviors included here and examine the relevance of additional behaviors speci c to particular infectious disease outbreaks. More speci c preventive medicine behaviors may enable organizations to identify a range of behaviors for front-line supervisors to emphasize in order to optimally support employee health and adaptation. The datasets generated and/or analyzed during the current study are not publicly available due to the sensitive nature of military training operations and ongoing data analysis, but are available from the corresponding author on reasonable request.

Competing Interests:
None to report