Not all individuals who were victims of a potential traumatizing event experience symptoms of an Acute Stress Reaction, and even less develop a Post-Traumatic Stress Disorder. In the United States, the National Comorbidity Survey found that during their whole lifetime statistically, 56% of Americans experience a trauma, and 8% develop PTSD (9).

 By conducting follow-up screenings of people who had experienced potentially traumatic events several factors could be identified which distinguished those who were able to recover from a traumatic experience, and those who developed PTSD or other problems following a traumatic event. Factors which were observed in individuals who experienced distinct symptoms of ASR, had difficulty to recover, or developed PTSD are called risk factors; factors which appeared to minimize ASR symptoms, to foster recovery, and to prevent PTSD development are called protective factors.

 Not surprisingly, a large amount of observations related to risk and protective factors were made in the military, as examples: Iversen et al (10) investigated risk factors for PTSD among UK Armed Forces personnel; Price (11) reported findings from the US National Vietnam Veteran’s Readjustment Study.

 It would exceed the scope of this chapter to describe all the factors which have been observed as increasing or lowering the threshold of experiencing traumatic reactions or developing PTSD. So in the following lists the focus will be laid on examples of risk and protective factors that may play a role in experiencing ASR onboard and possibly developing PTSD afterwards. More comprehensive overviews of risk and protective factors may be found in various guides in the literature and fact sheets in the internet.


Risk factors

 Risk factors related to the trauma:

 Kind of trauma:

  • Man-made traumas (e.g. accidents, terrorism, piracy, robbery). They may destroy the confidence in the reliability of other people.
  • Natural disasters (floods, tornados, rogue waves). Individuals concerned may experience a long-term sense of uncertainty, they may loose their conviction of safety and security, and they may lose their confidence in the future and their belief in the predictability in the world.

 Continuance of the trauma: short events vs. ongoing trauma such as being held as a hostage.

  • Severity and intensity of the event.
  • Feeling of not having control over the things going on, not having a chance to act.
  • Subjective appraisal of the event as threat to one’s own life.
  • Feeling of fear of death.
  • Dissociation.


Risk factors related to the person:

 Personality traits, e.g. compulsive or asthenic (8)

  • Previous trauma experience (may increase vulnerability of the individual)
  • Lack of satisfaction with one’s job and/or with one’s life
  • Lower rank
  • Low educational level
  • Lack of preparation or poor preparation for possible critical incidents
  • Poor coping skills


Risk factors related to the working and living conditions:

 Excessive workloads, e.g. tight deadlines, high time pressure, chronic sleep deprivation

  • Poor quality of leadership
  • Inadequate preparation and briefing
  • Lack of possibilities for recreation after the even

 Risk factors related to social relations (social environment):

 Communication difficulties due to personality and cultural differences

  • Isolation from one’s familiar social support network
  • Poor social relations within the crew
  • Lack of family relationship or poor relationship
  • Being single
  • Lack of good support system of family and friends
  • Lack of support in coping with the trauma


Risk factors related to the reactions from colleagues and superiors:

 Denying the opportunity to talk about trauma and feelings

  • Lack of support in coping
  • Devaluating reactions of colleagues or superiors (“It is his own fault, why did he act that way?”)
  • Demand from colleagues to pull oneself together
  • Lack of expression of appreciation by superiors or employer

 The risk factors should be controlled in order to decrease the vulnerability of humans. In addition, there are protective factors that affect the level above which an individual experiences ASR or develops PTSD.


Protective Factors

 The most prominent protective factor for coping with trauma is Antonovsky’s concept of sense of coherence (12[R1] ). Sense of coherence means manageability, comprehensibility and meaningfulness. These are important prerequisites for effectively coping with trauma. However, in this connection cultural differences have to be considered. According to the cognitive control theory by Frey and Jonas (13) members of the East Asian cultural circle prefer a secondary control strategy, i.e. they adapt by means of cognitive reframing to a seemingly unchangeable situation and they choose a rather fatalistic attitude.


Other protective factors


Protective factors related to the person:

 Psychological resilience

  • Having access to competent help
  • Ability to cope with stress effectively and in a healthy manner
  • High school degree or college education
  • Being resourceful
  • Having good problem-solving skills
  • Seeking help more likely
  • Holding the belief that there is something one can do to manage one’s feelings and to cope
  • Spirituality
  • Self estimation as survivor as opposed to victim
  • Helping others
  • Finding positive meaning in the trauma
  • Attitudinal components (pre-incident preparation)


Protective factors related to social relations (social environment):


  • Self-disclosure to loved ones
  • Having social support available
  • Being connected with others (family, friends)
  • Having the opportunity to get in contact with the family or with friends at home
  • Providing social support for coping


To know the risk and protective factors which may influence an individual’s trauma processing means being able to predict whether an individual has sufficient self-healing resources or whether suitable methods of crisis intervention have to be applied to prevent the development of PTSD.


In a research project the Institute for Clinical Psychology and Psychotherapy of the Cologne University developed a screening instrument by means of which the severity of risk factors and the availability of protective factors, respectively, can be assessed, and the necessary intervention can be recommended. This instrument is available for victims of violence in the general population – Cologne Risk Index – (14) and for the military – Cologne Risk Index – Military Version – (15). According to the risk factors the identified persons are assigned to one of three groups:


  • Group of Recovery: The individuals appear to have enough self-healing resources to cope with the traumatic event and to recover.


  • Switchers: The individuals are “on the verge of chronifying” (15). The process of recovery will probably be successful if no severe additional social and institutional stress is imposed on the affected persons following the traumatic situation.


  • High Risk Group: These individuals show a high potential risk of developing a Post Traumatic Stress Disorder.


For each group the necessary crisis intervention methods are assigned: For all three groups guidance for self-help; for the Recovery Group information about professional help, for the Switcher Group additional psychological aftercare, and for the Switcher Group and the High Risk Group psychotraumatological diagnostic and trauma therapy (for the Switcher Group only if needed).