Dissociation and disasters: A systematic review

Table 1 Studies of dissociation in adult disaster survivors

Disaster	Sample	Measures	Results
Ferry sinking (Baltic Sea 1994)[93,94]	42 survivors	3 ASD dissoc. items	3-mo dissoc. associated with 3-mo and 1-yr but not 14-yr posttraumatic stress
Earthquake (Haiti 2010)[28]	167 exposed volunteers	PDEQ	Mean 27-mo PDEQ score = 25. Dissoc. predicted posttraumatic stress symptoms and depression
Explosion (France 2001)[95-97]	430 survivors from local EDs	PDEQ	6-mo dissoc. posttraumatic stress at 6 and 15 mo but not 5 yr
Train crash (Israel 2005)[50]	53 survivors	DES, PDEQ	Scores higher in survivors with vs without fibromyalgia (9 vs 2; 20 vs 9)
Earthquake (San Francisco, CA 1993)[17]	100 exposed volunteer college students	SASRQ	All 5 dissoc. subscale scores higher at 1 wk than 4 mo
Explosion (Denmark 2004)[29,42]	169 evacuees	4 TSC dissociation items	Mean dissoc. Score = 6 (of 12). 3-mo dissoc. predicted 1-yr posttraumatic stress in women only and not 1-yr somatization
Floods/ mudslides (Italy 2009)[48]	287 exposed residents	DES, PDEQ	DES, difficulty identifying feelings, and externally oriented thinking predicted 27-mo PDEQ. PDEQ explained 44% of IES-R
Explosion (Belgium 2004)[98]	1027 exposed residents	PDEQ	5-mo dissociation predicted 5-mo (not 14-mo) posttraumatic stress
9/11, WTC (NYC 2001)[23]	1009 Manhattan residents, workers	1 DTS dissoc. item (event amnesia)	Event amnesia was least endorsed item (2%)
Earthquake (NZ, 2011)[40]	101 exposed treatment seekers	PDEQ (4 items)	Dissoc. predicted posttraumatic stress symptoms, anxiety at 2-8 wk
9/11 Pentagon (Washington, DC 2001)[44]	77 exposed military, civilian staff	PDEQ	Dissoc. associated with posttraumatic stress (18 vs 5) and alcohol use and negatively with perceived safety
3 technological accidents (Netherland)[99]	49 affected individuals	PDEQ, SDQ-P	20-d dissoc. did not predict 6-mo posttraumatic stress symptoms
Hurricane Katrina (New Orleans, LA 2005)[100]	65 exposed pet owners	PDEQ	Dissoc. associated with having to abandon pet (mean PDEQ = 30 vs 23), depression, acute stress, and posttraumatic stress symptoms.
Hurricane Katrina (New Orleans, LA 2005)[32]	117 people in mandatory evacuation zones	PDEQ	Mean PDEQ score = 12 (unknown timing). Dissoc. associated with property damage
Earthquakes; floods (Australia/NZ 2010-2011)[101]	662 exposed residents	PDEQ	Dissoc. associated with posttraumatic stress symptoms and negative beliefs about memory
Firestorm (Oakland/Berkeley 1991)[18,102]	94 referral center help seekers, 93 local students	SASRQ	1-mo dissoc. associated with 7-9-mo posttraumatic stress symptoms but not intrusions
9/11 WTC (NYC 2001)[24]	2001 NYC residents	2 DIS dissoc. panic attack items	4-5 mo dissoc. associated with posttraumatic stress symptoms, older age, female sex, non-white race, and fear of death or injury
Earthquake (Haiti 2010); tsunami (Japan, 2011)[103]	140 Haiti/12 Japan disaster exposed; 80 other trauma exposed	DES	Dissoc. scores (unknown timing) not different between trauma groups
Mass shooting (DeKalb, IL 2008)[25]	583 female university students	4 PDEQ items	2-wk dissoc. predicted 2-wk to 3-mo and 8-mo probable posttraumatic stress
Earthquake (Iran 2017)[80]	230 exposed volunteers from 2 cities	DES, PDEQ	3-4 mo dissoc. associated with posttraumatic stress
Earthquake (Turkey 2011)[26]	583 randomly sampled residents	DES (with Taxon)	2-yr DES Taxon membership = 25%. Dissoc. predicted posttraumatic stress symptoms, re-experiencing, avoidance, and hyperarousal but not functional impairment
Earthquake (Turkey 2011)[27]	317 volunteer college students	DES (with Taxon)	High (21%) DES Taxon membership (unknown timing). DES predicted posttraumatic stress symptoms. Pathological dissoc. mediated between posttraumatic stress symptoms and ADHD symptoms
Earthquake (Italy 2009)[35]	84 university student volunteers	14 TSI dissoc. items	7-yr dissoc. scores in exposed than unexposed. Dissoc. not associated with exposure
Hurricane Ike (Texas coast, 2008)[66,104]	75 older residents	PDEQ	Mean PDEQ = 11. Dissoc. associated with 3-mo posttraumatic stress but not 3-mo depression. Dissoc. not associated with posttraumatic stress trajectories
Tsunami (Indonesia 2004)[30]	660 evacuated Danish tourists	4 ERDTS dissoc. items	10-mo dissoc. predicted posttraumatic stress symptoms, depression
9/11 WTC (NYC 2001)[36,105]	75 exposed NYC residents	PDEQ, DES, CDS, CADDS	Mean PDEQ = 35, DES = 17. 3-mo dissoc. not associated 1-yr posttraumatic stress symptoms. Dissoc. not associated with exposure
Explosion (Taiwan 2015)[47]	116 burn survivors	SDQ	25-mo dissoc. associated with posttraumatic stress but not depression
Fire (Nether-lands, 2000)[31]	662 residents	PDEQ	Mean PDEQ = 24. 2-3 wk dissoc. not associated with 18-mo or 4-yr posttraumatic stress symptom severity
Fire and explosion (Netherlands 2001, 2004)[106]	94 disaster, 111 non-disaster burn survivors	3 ADS dissoc. items	1-wk dissoc. Disaster > others. Disaster: 1-wk dissoc. not associated with 12-mo posttraumatic stress

ADS[107]: Anxiety and Dissociation Scale; ASD: Acute stress disorder measure; CDS[105]: Cambridge Depersonalization Scale; CADDS[108]: Clinician Administered Dissociative States Scale; DES[20,21]: Dissoc.: Dissociation; Dissociative Experiences Scale; DIS[109]: Diagnostic Interview Schedule; DTS[110]: Davidson Trauma Scale; ERDTS[30]: Emotional Reactions During Trauma Scale; NYC: New York City; NZ: New Zealand; PDEQ[19]: Peritraumatic Dissociative Experiences Scale; SASRQ[111]: Stanford Acute Stress Reaction Questionnaire; SDQ[112]: State Dissociation Questionnaire; SDQ-P[113]: Somatoform Dissociation Questionnaire-Peritraumatic; TSC[114]: Trauma Symptom Checklist; TSI[115]: Trauma Symptom Inventory; WTC: World Trade Center.

Table 2 Studies of dissociation in child and adolescent disaster survivors

Disaster	Sample	Measures	Results
Hurricane Katrina (New Orleans, LA 2005)[41]	112 exposed students with ≥ 1 other trauma exposure	9 TSCC dissoc. items	4-mo to 7-yr dissoc. associated with posttraumatic stress symptoms, anger, anxiety, depression
Earthquake (Turkey 2011)[34]	738 exposed high school students	A-DES	6-mo dissoc. associated with posttraumatic stress, anxiety, prior mental health problems, metacognitions, but not with age, sex, disaster exposure, prior exposure to trauma
Earthquake (Turkey 1999)[33]	202 exposed, 101 unexposed children	11 TDGS dissoc. items	Exposed children had higher 4-5 mo perceptual distortions (1.3 vs 1.2), body-self distortions (1.1 vs 1.1) (range = 1-3 for both subscales)
Ferry disaster (South Korea 2014)[65]	57 child and adolescent survivors	3 PDEQ items	20-mo dissoc. associated with posttraumatic symptoms
Earthquake (China 2010)[116]	753 exposed middle school students	1 UPRI dissoc. item (derealization)	Majority (77%) positive for derealization. 6-mo derealization predicted PTSD

A-DES[117]: Adolescent Dissociative Experiences Scale; dissoc.: Dissociation; TDGS[33]: Traumatic Dissociation and Grief Scale; TSCC[118]: Trauma Symptom Checklist for Children; UPRI[119]: The University of California at Los Angeles Posttraumatic Stress Disorder Reaction Index.

Table 3 Studies of dissociation in exposed disaster workers

Disaster	Sample	Measures	Results
9/11, WTC (NYC 2001)[38]	90 disaster workers	PDEQ	Number of 2-3 wk dissoc. symptoms associated with probable ASD
Typhoon Haiyan (Philippines 2013)[37]	61 religiously, spiritually oriented humanitarian aid workers	MBI-HSS (5 depersonalization items)	Mean 8-mo depersonalization score = 1.1 (of 30). Depersonalization associated with negative religious coping but not with indirect exposure, direct exposure, or positive religious coping
Earthquake (Japan 2011)[43]	34 healthcare providers	MBI-HSS (5 depersonal-ization items)	Mean 2-yr depersonalization score = 0.6 (of 30). Depersonalization not associated with general mental health
Plane crash (Sioux City, IA 1989)[39]	207 exposed, 421 unexposed disaster workers	3 ASD dissoc. items	Number of 2-mo dissoc. symptoms associated with 13-mo posttraumatic stress but not depression. Any 2-mo dissoc. symptoms not associated with 13-mo posttraumatic stress or depression
9/11 WTC (NYC 2001)[46]	89 disaster responders	PDEQ	2-wk dissoc. negatively associated with perceived safety
Hurricane Katrina (New Orleans, LA 2005)[51]	441 rescue personnel	PDEQ	2-yr dissoc. associated with being single, exposure severity, physical victimization
Earthquake (Loma Prieta, CA 1989)[67,68]	198 exposed, 251 unexposed rescue personnel	PDEQ	1.5-yr dissoc. associated with 3.5-yr posttraumatic stress symptoms, intrusion, avoidance, hyperarousal
Earthquake (Italy 2009)[49,120]	285 healthcare workers at one hospital	MBI-HSS (5 depersonal-ization items)	Mean 6-yr depersonalization score = 1.1 (of 30) Depersonalization associated negatively associated with planning and positively with behavioral disengagement and self-distraction
Terror attacks (Norway 2011)[121]	238 rescue personnel	5-item scale developed by authors	8-11 mo dissoc. predicted posttraumatic stress
Fire (Netherlands 2000)[45]	66 ambulance personnel	PDEQ	2-3 wk dissoc. predicted 18-mo hostility, but not posttraumatic stress symptoms or depression

ASD: Acute stress disorder; dissoc.: Dissociation; MBI-HSS[22]: Maslach Burnout Inventory–Human Services Survey; NYC: New York City; NZ: New Zealand; PDEQ[19]: Peritraumatic Dissociative Experiences Scale; WTC: World Trade Center.