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van CCT (UK)

van CCT (UK)

Freeze! Nationaal Politie Onderzoek

- candidate number27152
- NTR NumberNTR6355
- ISRCTNISRCTN no longer applicable
- Date ISRCTN created
- date ISRCTN requested
- Date Registered NTR1-mei-2017
- Secondary IDsNL48861.072.14  IRB Nijmegen
- Public TitleFreeze! Nationaal Politie Onderzoek
- Scientific TitlePOLICE-IN-ACTION: The role of automatic defensive responses in the development of posttraumatic stress symptoms
- hypothesisIn line with the Research Domain Criteria (RDoC), participants will be stratified based on their (trauma-related changes in) automatic defensive responses. We hypothesize that this stratification will be associated with the development of specific trauma-related symptoms.
- Healt Condition(s) or Problem(s) studiedPost traumatic complaints
- Inclusion criteria1. Between 18 and 45 years of age
2. Normal or corrected to normal vision
3. Normal uncorrected hearing
4. Body mass index between 18.5 and 30
5. Willingness and ability to give written informed consent
- Exclusion criteria1. Average use of > 3 alcoholic beverages daily
2. Average use of psychotropic medication or recreational drugs weekly or more
3. Use of psychotropic medication
4. Recreational drugs use within 72 hours prior to testing, or alcohol use within 24 hours prior to testing
5. Current psychiatric or neurological disorder, or within the last three months.
6. Regular use of systemic corticoids
7. Metal objects or fragments in or around the body
8. Medical plaster that cannot or may not be taken off
9. History of or current neurological treatment
10. History of or current endocrine treatment
11. History of head surgery
12. Current periodontitis
13. Claustrophobia
14. Epilepsy
15. Females participants: pregnancy
Control participants only:
16. Experience in law enforcement or military
17. Occupation involving potential trauma exposure, such as military or healthcare occupation
- mec approval receivedyes
- multicenter trialno
- randomisedno
- groupParallel
- Type2 or more arms, non-randomized
- Studytypeobservational
- planned startdate 17-nov-2014
- planned closingdate1-jan-2018
- Target number of participants425
- InterventionsNot applicable. Observational study about the effects of trauma exposure during emergency aid in police recruits (N=340). A well-matched control group of civilians (N=85) is also included, wich are not frequently exposed to potentially traumatic events.
- Primary outcome1. Associations between behavioral, psychophysiological, endocrine and neural automatic defensive responses at baseline (pre-exposure, wave 1) and development of trauma-related psychopathology after trauma exposure during emergency aid (difference wave 2 - wave 1) in police recruits. Trauma-related symptoms are measured with the PTSD checklist for DSM-5 (PCL-5; PTSD symptoms), impulsive/premediated aggression scale (IPAS; aggression symptoms) and reactive proactive aggression questionnaire (RPQ; aggression symptoms).

2. Associations between changes in behavioral, psychophysiological, endocrine and neural automatic defensive responses after trauma exposure (difference wave 2 - wave 1) and development of trauma-related psychopathology after trauma exposure (difference wave 2 - wave 1) in police recruits.
- Secondary outcome1. Associations between (changes in) automatic defensive responses and secondary health outcome measures (e.g. anxiety, depressive symptoms) as a consequence of trauma exposure during the emergency aid. 2. Associations between (changes in) secondary biological outcome measures (e.g. epigenetics) and development of trauma-related psychopathology after trauma exposure during the emergency aid. 3. Potential moderating effects of individual differences, such as genetic variation (e.g. genetics, epigenetics, microRNA), endocrine markers in saliva and hair, physical fitness, and other individual characteristics (e.g. social support, attachment style, history of (childhood) traumatic events etc.) on (the association between (changes in)) automatic defensive responses and development of trauma-related psychopathology.
- TimepointsAssessment of automatic defensive responses pre-trauma exposure (wave 1) and post-trauma exposure, after emergency aid experience at 15 months follow-up (wave 2).
- Trial web site
- statusinclusion stopped: follow-up
- Sponsor/Initiator Donders Institute for Brain, Cognition, and Behaviour, Centre for Cognition, Radboud University Nijmegen
- Funding
(Source(s) of Monetary or Material Support)
- Publications-
- Brief summaryControl over our automatic tendencies is often compromised in challenging situations when people fall back on automatic defensive responses, such as freeze-fight-flight reactions. Difficulties in controlling automatic defensive responses may not only impair split-second decisions under acute threat, but also increase the risk for and persistence of posttraumatic stress disorder (PTSD) symptoms. However, previous PTSD research has largely neglected the role of these automatic defensive responses in the development and maintenance of PTSD. Therefore, the ‘Police-in-Action’ study aims to investigate the role of automatic defensive responses in the development and maintenance of PTSD symptomatology after trauma exposure.

In this prospective study, 340 police recruits from the Dutch Police Academy will be tested before (wave 1; pre-exposure) and after (wave 2; post-exposure) making the transition from the relatively safe environment of theoretical training to their first emergency aid experiences. Our main aim is to investigate whether automatic defensive responses, measured at the behavioral, psychophysiological, endocrine and neural level, may predict, or change in response to, the development of PTSD symptoms in police recruits after trauma exposure. Disentangling predisposing from acquired neurobiological abnormalities associated with the development PTSD symptoms may ultimately improve screening for individuals at risk for developing PTSD, and offer valuable targets for (early preventive) interventions for PTSD.
- Main changes (audit trail)
- RECORD1-mei-2017 - 11-jun-2017

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