International Military Leaders Survey on Operational Stress

Transcription

1 MILITARY MEDICINE, 173, 1:10 16, 2008 International Military Leaders Survey on Operational Stress Amy B. Adler, PhD*; Paul Cawkill, MSc ; Lieutenant Colonel Coen van den Berg ; MC Philippe Arvers ; Major José Puente ; Lieutenant Colonel Yves Cuvelier ABSTRACT Despite the importance of military leaders in moderating the impact of deployment stressors on unit members, little attention has focused on the training leaders receive in managing unit stress. As part of a NATO Research Panel (Human Factors and Medicine (HFM)-081/Research and Technology Organization Task Group (RTG)), 16 nations participated in a needs assessment survey of military leaders who had returned from an operation within the previous 2 years. Findings from 172 leaders emphasized the lack of training specifically geared for leaders to address operational stress issues for unit members and their families and the need for integrated mental health support across the deployment cycle. In general, most leaders regarded stress-related mental health problems as normal and were supportive of help-seeking. The information obtained here was used to develop a Human Factors and Medicine -081/RTG Leader s Guide on operational stress. *U.S. Army Medical Research Unit Europe, APO AE Human Systems Group, Defence Science & Technology Laboratory (Dstl), Farnborough, Hants, GU14 0LX U.K. Netherlands Defence Academy, Faculty of Military Sciences, Military Behavioural Sciences and Philosophy, PO Box , 4800 PA Breda, The Netherlands. Départment des Facteurs Humains, Pôle Psycho-sociologie des contraintes opérationelles, Centre de Recherches du Service de Santé des Armées, CRSSA, BP87, La Tronche Cedex, France. Inspección General de Sanidad-Unidad de Psicologia (Joint Medical Office, Unit of Psychology), Hospital Central de la Defensa, Clínicas Especiales, 5 a Planta, Glorieta del Ejército s/n, Madrid, Spain. DOO-SAO, Kwartier Koningin Astrid, Bruynstraat 200, 1120 Neder- Over-Heembeek, Brussels, Belgium. Portions of this article were presented at the 2006 NATO Research and Technology Organization Human Factors and Medicine 134 Symposium, Human Dimensions in Military Operations: Military Leaders Strategies for Addressing Stress and Psychological Support, April 24 26, 2006, Brussels, Belgium and the 2006 Meeting of the International Society for Traumatic Stress Studies, November 4 7, 2006, Hollywood, CA. The views of the authors do not necessarily represent their respective Department of Defence or government. This manuscript was received for review in March The revised manuscript was accepted for publication in August INTRODUCTION Deployments are a source of potential stressors for military personnel and their families. The stressors begin at predeployment, continue through the deployment phase, and include the postdeployment period of adjustment. 1 Such stressors may have implications for individual job performance, 2 the health and well-being of military personnel, 3 the functioning of military families, 4 and the desire of military personnel to remain in the military. 5 While researchers have identified individual variables that moderate the impact of deployment-related stressors, 6,7 studies have also examined how leaders influence the impact of deployment stressors on unit members. For example, positive outcomes following deployment have been associated with confidence in senior leadership, 8 the degree to which leaders clarify goals and provide structure, 9 and leader acknowledgment of soldier sacrifices. 10 Such findings underscore the role of leaders in moderating the impact of deployment on outcomes of importance to unit members, leaders, and the military organization. Despite the importance of leaders influencing the health and well-being of unit members during deployment, we are aware of no systematic assessment of how leaders are trained to address operational stress issues or their satisfaction with this training. To assess leader training in mental health support across the deployment cycle, NATO s Human Factors and Medicine (HFM)-081/Research and Technology Organization Task Group (RTG) conducted a multinational survey of operational leaders. The NATO HFM-081/RTG Stress and Psychological Support in Modern Military Operations Group evolved from an exploratory team (HFM-ET016) in 2002 and was established in April The primary goal was to provide military leaders with information and practical guidelines on stress and psychological support to enhance effectiveness in operations. HFM-081 developed a survey to assess leader preferences for such guidance. Questions were also asked about how leaders viewed mental health problems because stigma had been identified as an important issue for military personnel returning from deployment 3 although commanders seem to have relatively tolerant attitudes toward combat stress reactions. 11 The aim of the survey was to assess (1) what kind of support and training military units and leaders received for dealing with stress-related problems in their unit across the deployment cycle; (2) what support and training they wanted to receive about stress-related problems; and (3) leader attitudes toward mental health-related problems. METHOD Procedure Sixteen NATO and Partnership-for-Peace (PfP) nations participated in the project between June 2005 and January 2006, 10 MILITARY MEDICINE, Vol. 173, January 2008

2 which included either a face-to-face interview or a postal questionnaire depending on the logistical requirements for each nation. In all, the survey or interview took approximately 30 to 45 minutes to complete and was conducted in the national language of the participant. Selection for the survey was based on a convenience sample although participants needed to have been in a leadership position (enlisted or officer) on operations sometime in the last 2 years. Responses were not linked with specific names or identifying information and participation in the study was voluntary. Data were aggregated across nations, thereby also preserving the anonymity of specific nations. Sample Of the 19 nations comprising HFM-081/RTG, there were returns from 16 nations (Table I). Of the 172 responses, the majority (97%) of responses were from Army personnel. Ranks ranged from sergeant to colonel; 78.5% were officers. All but two participants were men. Length of service ranged from 3 to 35 years with a mean of 16 years (SD 8.08). Respondents identified their primary military role as infantry (56.2%), artillery (12.4%), engineering (7.1%), or armored (6.5%). Half of the respondents had been on one deployment; 30% had been on two deployments. In all, 79% had only been on peacekeeping deployments and 16% had been on combat deployments. The majority of deployment locations included Afghanistan, Bosnia, Kosovo, and the Gulf/Iraq. Measures All of the questions were designed specifically for this needs assessment, and a subset of questions are included in the present analysis. The questions and sample responses are presented in Table II. TABLE I. NATO and PfP Nations Participating in Survey Nation No. Surveyed Austria 10 Belgium 17 Bulgaria 11 Canada 5 Czech Republic 10 Denmark 5 France 17 Lithuania 11 Luxembourg 10 The Netherlands 15 Romania 10 Spain 14 Slovakia 10 Sweden 4 United Kingdom 9 United States 14 Total 172 Psychological Support Respondents were asked (1) what kinds of psychological training and support their unit received for psychological or stress-related problems; (2) what kinds of training and support they, as leaders, received for mental health-related issues; and (3) what elements of training and psychological support leaders would like to see changed. These questions were asked for each phase of the deployment cycle: predeployment, deployment, and postdeployment. Family Support Respondents were asked (1) what kinds of support and training family members received; (2) what kinds of support and training they, as leaders, received for handling family-related problems; and (3) what training and support they would like in terms managing family member stress. Again, these questions were asked for each phase of the deployment cycle. General Attitudes Leaders were asked who they considered to be responsible for the psychological readiness of unit members. Leaders were also asked what they thought of unit members who had stress-related problems and unit members who sought services for stress-related problems. Analysis Strategy The goal of the data analysis was to identify common themes that bridged across the participating NATO nations. Given this goal, specific national issues were not highlighted and themes were mentioned if they were reported by at least two nations represented in the sample. Direct quotes were used, however, as illustrations. RESULTS Psychological Support across the Deployment Cycle Predeployment Unit Training and Support. At least one individual from every nation in the survey reported some predeployment unit briefing, group instruction, or education related to psychological stress on operations. Nevertheless, respondents from nine different nations reported that their units received no predeployment psychological preparation. Thus, there appears to be some variability within nations as to whether units receive predeployment stress-related training. In the case of respondents from at least two nations, the lack of preparation appeared to be due to the fact that the deployment occurred on short notice. The topics of training included the psychological stages of deployment, normalizing responses and reassuring unit members about their own reactions, identifying individuals at risk for suicide, dealing with family issues, and dealing with combat stress. Respondents from five nations mentioned having training exercises that incorporated dealing with psychological stress in some fashion. MILITARY MEDICINE, Vol. 173, January

3 TABLE II. Questions and Sample Responses to the Military Leaders Survey Survey Question Psychological support at predeployment What kind of psychological preparation did your unit receive prior to your last deployment in order to cope with any psychological or stress-related problems that might occur during the operation/mission? Did you, as one of the unit leaders, receive any specific training or preparation for supporting subordinates in the event of encountering stress-related problems during the operation/mission? Are there any elements of the current predeployment psychological preparation that you would like to see changed and/or improved upon? Psychological support during deployment What kind of psychological support did your unit receive during your last deployment in order to cope with psychological or stress-related problems that might occur during the operation/mission? Did you, as one of the unit leaders, receive any specific support for assisting unit members if they encountered stress-related problems during the operation/mission? Are there any aspects of the psychological support provided during operations that you would like to see changed or improved upon? Psychological support at postdeployment What kind of psychological support did your unit receive after the last deployment in order to cope with psychological or stress-related problems that might occur after the operation/mission? Did you, as one of the unit leaders, receive any specific support for assisting unit members with stress-related problems following the operation/mission? Are there any aspects of the psychological support provided postdeployment that you would like to see changed or improved upon? Military families What kind of psychological support was received by the unit family members before, during, and after the last deployment in order to cope with psychological or stress-related problems that might occur? When thinking of the current psychological support given to families within your nation, are there any changes/improvements you would like to see implemented? General attitudes Who do you think should be responsible for preparing military personnel for operational psychological readiness? What do you think of military personnel who suffer stress-related problems on or after deployment? What do you think of military personnel who seek services for stress-related problems? Sample Responses We had psychological education about stress and how to cope with it in different situations. Just a 30 to 60 minute briefing on signs and symptoms of combat stress. None. No course or training. Preparation based on personal experience. Nothing received specific to that deployment. Having former leaders explain, based on their experiences from missions, what to expect on a mission, maybe by using cases to illustrate different situations. There is a certain need of predeployment training at all levels. It should be aimed at dealing with the problems during the mission and effective management of the team in a conflict or crisis. Support from comrades. Military psychologist helped to solve individual problems. Yes, from military leaders with higher military ranks. A visit from a psychologist after an accident (happened once). It would be better if the psychologist had more practical insight concerning the work leaders do during a mission and by that be able to relate more to the situations leaders might face during a mission. Chaplains need more training as they are first line care/counselors. One was good, the others had no training. As part of a post-deployment reintegration period, we received a series of briefings to help cope with reunification and postdeployment stressors. Two surveys. Reintegration briefing. No. Nothing for leaders. Suicide prevention training what to look for in soldiers. Optimally, psychologists could be standing by at base to assist if necessary during the homecoming procedure. Currently, when a unit returns home some personnel are immediately dispatched to another unit. This means they have no one to talk to about the highs and lows relating to their recent operation. You need 3 months together as a unit during postdeployment. We received postoperation handouts on separation from family. But there was no guidance for me as a leader on how to cope with families... A letter and a support handbook. I think we have it right for cohesive units/subunits, but for augmentees we are failing in our family support. We don t target reintegration at the right time we target the honeymoon phase when we first get back. They re tired and they go on block leave and then come back to work. Then 90 days later the problems become real again. The Commanding Officer but he needs a professional advisor to help him. Commanders in close cooperation with psychologists. This is not a disease but a moment of inner crisis. They need help rather than being returned home or decommissioned. Seeking help demonstrates courage, strength, and maturity, and demands great respect from others. 12 MILITARY MEDICINE, Vol. 173, January 2008

4 Leader Training. Respondents from 15 of the 16 nations surveyed reported receiving no training specifically geared toward preparing leaders to handle stress-related problems in their unit. When training was mentioned, it was described as independent of deployment preparation. Respondents from eight nations reported participating in some kind of staff course or military academy course, and respondents from three nations took university courses related to stress and mental health. In terms of informal mechanisms of support, respondents from five nations reported that they relied on their own deployment experience. As one leader mentioned, he received nothing formal but experience... was good preparation. In addition, respondents from three nations reported talking with leaders who had deployment experience. Training Recommendations. There was agreement across many nations that predeployment psychological training be part of preparing unit members for deployment. The need for leader-specific training was also acknowledged. Leaders identified themselves as having a unique role: they are often the first to deal with a critical incident, have to manage a team in crisis, and have to identify psychological problems among peers. As one leader noted, it was difficult... to recognize soldiers having problems when they are [also] your friend. Respondents were consistent in their recommendation that the training be oriented toward specific practical information and based on case examples. Recommendations included providing useful tips, being taught specific tools for handling stress, and examples, real situations, and practical advice. It was also suggested that this guidance involve experienced leaders. There was a range of topics suggested for such training including psychological and physiological responses to stress, critical incident handling, traumatic and combat stress, symptom recognition, and dealing with death. In terms of dealing with death, recommendations included dealing with friendly fire fatalities and injuries, mission casualties, and lectures on death (what to do, follow-up, and help for the platoon). Respondents from many nations commented that mental health professionals needed to be available and integrated into or known by the unit. As one leader said, I d like professional advice on call, at hand to deal with individual cases. Someone who was able, physically, to go out to the unit and help. During Deployment Unit Training and Support. Respondents from 11 nations consistently reported receiving several different kinds of support during deployment. This support was provided by a range of specialists including social workers, psychiatric nurses, psychologists, chaplains, and medical professionals. Examples of this support included advice, individual consultations with targeted subgroups, and group debriefing/ defusing sessions. This support was often in response to a specific traumatic event (e.g., helicopter crash, ambush with casualties, accident involving death of a soldier). Nevertheless, leaders from four nations consistently reported receiving little, if any, formal mental health support on deployment and described receiving support from fellow unit members. Leader Training. Military leaders from 10 nations generally said that they did not receive any specific support or training as leaders for assisting unit members during deployment. Five nations reported receiving only minimal support. None of the nations had respondents who consistently reported receiving support for assisting unit members dealing with stress. In the few cases where leader support was offered, it was in the form of identifying individuals with mental health problems, addressing risk of suicidal behavior, and personal support from friends. In general, such support was provided by mental health professionals, chaplains, and other leaders. Training Recommendations. There were many suggestions about ways to improve the psychological support provided during operations in an international setting. Respondents from four nations recommended training for working in a multinational environment, both in terms of dealing with the local culture and in terms of working with militaries from other nations and commanding foreign troops. Similarly, several respondents noted the need for a plan to overcome language barriers when psychological support was provided by someone from another nation. There were consistent concerns that the mental health professionals providing support to unit members during the deployment be adequately trained and adopt a proactive role in being integrated with the unit. It was also recommended that mental health professionals be credible in terms of knowing the unit and the military environment. Leaders also recommended that chaplains, who were considered an excellent source of support, receive more formal training in mental health. In addition, leaders wanted mental health professionals to be embedded with their unit or mobile so that even those units in relative isolation could access services. Leaders noted that many of the unit problems were related to home front issues, not just operational issues and mental health support needed to handle both issues. Leaders also suggested training in communication (e.g., to integrate new members into unit), peer training (e.g., to provide mental health support during deployment), alcohol problems, specific operations, and/or subgroups (e.g., transportation units which are not trained for combat). Several respondents recommended routine meetings with mental health professionals to address these issues and individual assessment during the mission to identify those having problems. Two individuals from two nations remarked that mental health support was not needed or was of no interest. Postdeployment Unit Training and Support. Individuals from 14 of 16 nations reported some type of formal psychological support related to returning from deployment. This support included an array of mechanisms: individual interviews with military mental health professionals, briefs on homecoming, debriefings, surveys, and some period of time set aside for decompression. Only 2 of the 16 nations in the survey consistently reported no kind of support. Several respondents commented on the importance of receiving psychological support and the need to extend this support to families. Leaders also distinguished between the need for postdeployment mental health support following a benign tour com- MILITARY MEDICINE, Vol. 173, January

5 pared to a high-stress deployment. In the event of a benign tour, postdeployment psychological support was not necessarily considered critical but in the event of a high-stress deployment, it was considered to be very important. Only 1 respondent (of 172) said that mental health support was not needed postdeployment. Leader Training. The majority of respondents from 15 of the 16 nations reported that there was no specific training for leaders for managing the psychological stress of unit personnel at postdeployment. Besides 1 nation that had such training, 6 individual respondents from other nations reported receiving some form of briefing about postdeployment stress geared for leaders (e.g., suicide, the signs and symptoms of post-traumatic stress disorder). There was general agreement that military leaders were the first line of defense for identifying mental health problems in unit personnel (e.g., It is down to the unit leader to make the first assessment ), but when individuals were not deployed as part of an intact unit or otherwise dispersed, providing this support was often difficult. Others described the importance of maintaining an informal network to track the adjustment of former unit members and knowing whom to contact in the event a unit member had a psychological problem. Training Recommendations. Leaders commented on the need for decompression time before reintegration (e.g., to relax with the first beer without the home front ). Respondents from seven nations also suggested that psychological support be extended beyond the immediate postdeployment period and be provided at least 3 to 6 months postdeployment. Consistent with this theme, maintaining unit integrity for at least 3 months after homecoming was an important issue for respondents from at least four nations. Unit integrity was described as facilitating adaptation back home, ensuring unit members had friends with whom to talk, and enabling leaders to assess the adjustment of their unit members more easily. Respondents from several nations mentioned the importance of informal support networks in helping individuals cope with stress during the postdeployment phase. In addition, several respondents recommended providing information on postdeployment psychological adjustment to the unit as a whole and including family members in training about the signs and symptoms of stress-related problems. Respondents from several nations recommended structured individual interviews with military personnel, especially following particularly stressful or dangerous deployments. Respondents from several nations suggested that military mental health professionals be available (e.g., standing by, meeting with unit members) during homecoming and after. Having a mental health professional identified as a resource for a unit was not enough; respondents commented that military mental health professionals need to make themselves visible and accessible. For example, mental health professionals should be present during unit social gatherings. Some respondents recommended that leaders receive support from mental health professionals in recognizing and dealing with their own stress reactions. As one respondent recommended to mental health professionals, Talk to leaders and see how they are doing as it is pretty stressful for NCOs [noncommissioned officers] and officers. Military Families Family Training and Support Responses from 50 military leaders indicated that family members of deploying personnel received support. Families typically received information that was designed to help them have contact with one another and to assist them in navigating the military system. Respondents also reported that family members were typically briefed about what to expect in dealing with deployment and the impact of a deployment on military families. Leaders primarily described family support during deployment as focused on facilitating communication home including phone calls, the Internet, and webcams. Communication about the unit was supported through websites, newsletters, family briefings, and phone circles. That said, 46 respondents reported not being aware of family support or that no family support was provided. Of the 24 leaders who reported family support at postdeployment, this support included reintegration briefings, homecoming meetings, group sessions with families, and clinical support for those with significant difficulties adjusting. Support and Training Recommendations Leaders recommended contact between the unit and families be improved during the predeployment and deployment phases and that individuals not deployed as part of an intact unit be provided more support. Suggestions included conveying realistic, but not alarming, information about the mission to families, providing regular contact from the unit, and providing information geared to children. Respondents from a number of nations raised the issue of providing practical support to spouses, as spouses often have to deal single-handedly with family issues during the deployment. Several respondents suggested that professional staff like psychologists and chaplains be available for military families if needed. Leaders recommended that postdeployment training for families occur after the initial reintegration honeymoon period. General Attitudes Responsibility for Psychological Readiness Leaders were asked who was responsible for the psychological readiness of unit members. The most common response, reported by leaders from eight nations, was that commanding officers (COs) should be responsible. Respondents considered COs from platoon to battalion level to have ultimate responsibility for the unit and the necessary experience and knowledge of the military required to know the needs of the individual and the organization as a whole. Leaders also noted that COs are in close proximity and have daily contact with their subordinates. The second most common response, mentioned by leaders from six nations, was that psychologists were responsible for 14 MILITARY MEDICINE, Vol. 173, January 2008

6 the psychological readiness of the unit. Psychologists were seen as experts who had the necessary in-depth knowledge and experience relevant to this area. Medical staff was the third most common response. Approximately 50 military leaders noted that both the CO and psychologist or medic were responsible. Options receiving 10 or fewer responses included the chaplain, military personnel themselves, and personnel staff. Attitudes Related to Stigma Leaders were asked what they thought of unit members with mental health problems. Frequent comments from 11 nations reflected the perspective that stress was normal, and that everybody suffers to a certain degree, although the majority cope and deal with it. Some leaders from eight nations were less tolerant of mental health problems. They noted that having stress problems could be a way unit members try to get out of work, could harm one s career, or could reflect a deficiency in predeployment selection, and that these individuals should not be allowed to deploy or should be sent home. Other comments reflected the belief that individuals suffering from stress were sick and needed help. Leaders were also asked what they thought of unit members who sought mental health services. Most were supportive with such statements as, It is the best/right/ smart/responsible/reasonable/sensible thing to do. Respondents from three nations saw help-seeking as a sign of strength, courage, and maturity. Also, several military leaders stated that they regarded unit members with more respect and understanding when unit members acknowledged their problems and recognized that they needed help. The potential for stigmatization was mentioned by respondents from three nations and the concern that helpseeking behavior would lead to discharge was mentioned by respondents from two nations. DISCUSSION Results from an international survey of experienced military leaders found that while there were national differences in terms of the degree of mental health support provided to unit members across the deployment cycle, most nations had some kind of mental health support for unit members and their families. There was greater consensus, however, that leaders were provided little training in addressing operational stress issues. The majority of leaders were interested in receiving training and preferred concrete, specific information related to recognizing and managing psychological stress on deployment. Another consistent theme from the survey was that most leaders saw themselves as responsible for the psychological readiness of their unit members and wanted to work together with military mental health professionals to achieve this goal. In general, leaders also wanted military mental health professionals to be more visible and integrated with their unit. The majority of leaders surveyed saw the presence of stressrelated problems on deployment as normal, and generally agreed that help-seeking behavior was a positive step, although other leaders disagreed. This survey was a needs assessment that relied on a convenience sample. Respondents are not necessarily representative of their nation s military leaders. Despite the potential for a biased sample, this survey was the first needs assessment of its kind and included a range of ranks and deployment experiences. The approach can serve as a model for conducting multinational needs assessments with other NATO RTGs, ensuring that programs developed are responsive to operational leaders requests. In addition, the results from this survey suggest the need for developing training programs on operational stress designed specifically for leaders. Follow-up research should assess the efficacy of such programs both within and across nations. As an initial step, the NATO Task Group has integrated the recommendations from the military leaders survey into A Leader s Guide to Psychological Support Across the Deployment Cycle. 12 This guide represents the first concerted effort to target leaders with information about managing stress-related problems in unit members. The guide is general enough to apply to the range of NATO and PfP nations and includes information on stress-related reactions, mental health and morale assessments, families, and the role of military leaders in supporting unit member mental health. Throughout, firsthand accounts exemplify the issues discussed and practical information is provided as highlights. The goal of such a guide is to translate psychological information into a useful product for operational leaders and simultaneously increase interoperability by providing NATO and PfP leaders with a common understanding of stress-related concerns. REFERENCES 1. Wiens TW, Boss P: Maintaining family resiliency before, during, and after military separation. In: Military Life: The Psychology of Serving in Peace and Combat. Vol III. The Military Family, pp Westport, CT, Praeger Security International, Driskell JE, Salas E, Johnson JH: Decision making and performance under stress. In: Military Life: The Psychology of Serving in Peace and Combat. Vol I. Military Performance, pp Westport, CT, Praeger Security International, Hoge CW, Castro CA, Messer SC, McGurk D, Cotting DI, Koffman RL: Combat duty in Iraq and Afghanistan, mental health problems, and barriers to care. N Engl J Med 2004; 351: Peebles-Kleiger MJ, Kleiger JH: Re-integration stress for Desert Storm families: wartime deployments and family trauma. J Trauma Stress 1994; 7: Huffman AH, Adler AB, Dolan CA, Castro CA: The impact of operations tempo on turnover intentions of Army personnel. Mil Psychol 2005; 17: Britt TW, Adler AB, Bartone PT: Deriving benefits from stressful events: the role of engagement in meaningful work and hardiness. J Occup Health Psych 2001; 6: Dolan CA, Adler AB: Military hardiness as a buffer of psychological MILITARY MEDICINE, Vol. 173, January

7 health on return from deployment. Milit Med 2006; 17: Gal R, Manning FJ: Morale and its components: a cross-national comparison. J Appl Soc Psych 1987; 17: Bliese PD, Halverson RR: Using random group resampling in multilevel research: an example of the buffering effects of leadership climate. Leadership Q 2002; 13: Thomas JL, Castro CA: Organizational behavior and the US peacekeeper. In: The Psychology of the Peacekeeper: Lessons from the Field, pp Westport, CT, Praeger Press, Inbar D, Solomon Z, Spiro S, Aviram U: Commanders attitudes toward the nature, causality, and severity of combat stress reaction. Mil Psychol 1989; 1: Human Factors and Medicine (HFM) Panel/Research and Technology Organization (RTO), HFM 081 Task Group: A Leader s Guide to Psychological Support across the Deployment Cycle. Technical Publication, NATO RTO, Neuilly-sur-Seine, France, MILITARY MEDICINE, Vol. 173, January 2008