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HoppenTH, etal. BMJ Global Health 2021;6:e006303. doi:10.1136/bmjgh-2021-006303
Global burden of post- traumatic stress
disorder and major depression in
countries affected by war between 1989
and 2019: a systematic review and meta-
analysis
Thole H Hoppen ,1 Stefan Priebe,2 Inja Vetter,1 Nexhmedin Morina1
Original research
To cite: HoppenTH, PriebeS,
VetterI, etal. Global burden
of post- traumatic stress
disorder and major depression
in countries affected by war
between 1989 and 2019: a
systematic review and meta-
analysis. BMJ Global Health
2021;6:e006303. doi:10.1136/
bmjgh-2021-006303
Handling editor Seye Abimbola
►Additional supplemental
material is published online only.
To view, please visit the journal
online (http:// dx. doi. org/ 10.
1136/ bmjgh- 2021- 006303).
Received 13 May 2021
Accepted 20 July 2021
1Institute of Psychology,
University of Münster, Münster,
Germany
2Unit for Social and Community
Psychiatry, Queen Mary
University of London, London,
UK
Correspondence to
Dr Thole H Hoppen;
thoppen@ uni- muenster. de
© Author(s) (or their
employer(s)) 2021. Re- use
permitted under CC BY- NC. No
commercial re- use. See rights
and permissions. Published by
BMJ.
ABSTRACT
Objective Extensive research has demonstrated high
prevalences of post- traumatic stress disorder (PTSD)
and major depression (MD) in war- surviving populations.
However, absolute estimates are lacking, which
may additionally inform policy making, research and
healthcare. We aimed at estimating the absolute global
prevalence and disease burden of adult survivors of
recent wars (1989–2019) affected by PTSD and/or MD.
Methods We conducted a systematic literature search
and meta- analysis of interview- based epidemiological
surveys assessing the prevalence of PTSD and/or MD in
representative samples from countries with a recent war
history (1989–2019). Drawing on the war denition and
geo- referenced data of the Uppsala Conict Database
Programme and population estimates of the United
Nations for 2019, we extrapolated the meta- analytic
results to absolute global numbers of affected people.
Drawing on disability- adjusted life years (DALYs) data of
the Global Burden of Diseases Study 2019, we further
calculated the PTSD- associated and MD- associated
DALYs.
Results Twenty- two surveys (N=15 420) for PTSD,
13 surveys for MD (N=9836) and six surveys on
the comorbidity of PTSD and MD (N=1131) were
included. Random effects meta- analyses yielded point
prevalences of 26.51% for PTSD and 23.31% for MD.
Of those affected by PTSD, 55.26% presented with
comorbid MD. Prevalence rates were not significantly
associated with war intensity and length, time since
war, response rate or survey quality. The extrapolation
yielded 316 million adult war- survivors globally who
suffered from PTSD and/or MD in 2019. War- survivors
were almost exclusively living in low/middle- income
countries (LMICs) and carried a burden of 3 105 387
and 4 083 950 DALYs associated with PTSD and MD,
respectively.
Conclusions Since LMICs lack sufcient funding and
qualied professionals to provide evidence- based
psychological treatments for such large numbers of
affected people, alternative and scalable strategies using
existing resources in primary care and communities are
required. Research is required to assist upscaling.
INTRODUCTION
Meta- analyses demonstrate high preva-
lence rates of post- traumatic stress disorder
(PTSD) and major depression (MD) in
Key questions
What is already known?
►Several meta- analyses of epidemiological surveys have
demonstrated high prevalences of post- traumatic stress
disorder (PTSD) and major depression (MD) in war-
surviving populations.
►However, absolute global estimates of prevalence and
disease burden are lacking.
►Estimates in absolute numbers may inform policy mak-
ing, research and healthcare beyond percentages.
What are the new ndings?
►In this systematic review and meta- analysis that includ-
ed 41 surveys, random effects meta- analyses yielded a
point prevalence of 26.51% for PTSD and 23.31% for
MD.
►Of those affected by PTSD, 55.26% presented with co-
morbid MD.
►The extrapolation yielded about 316 million adult war
survivors who experienced PTSD and/or MD in 2019
residing in 43 war- ridden countries with a war histo-
ry between 1989 and 2019 (almost exclusively low/
middle- income countries (LMICs)).
►PTSD and MD were associated with about 3 million and
4 million disability- adjusted life years, respectively.
What do the new ndings imply?
►The number of war survivors experiencing PTSD and/or
MD creates a massive mental health burden, which is
primarily borne by LMICs.
►Tailored approaches for LMICs contexts are necessary to
address the presented vast mental health burden.
►Low- cost and scalable solutions that build on available
resources are recommended as well as multidisciplinary
research to guide evidence- based upscaling.
►The ndings generally illustrate the importance of
peace- building and maintenance.
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2HoppenTH, etal. BMJ Global Health 2021;6:e006303. doi:10.1136/bmjgh-2021-006303
BMJ Global Health
war- affected populations with pooled estimates ranging
from 15.3% to 30.6% for PTSD and 10.8% to 30.8% for
MD.1–4 However, there is a lack of prevalence estimates
and disease burden estimates in absolute numbers.
Such absolute estimates are important for three major
reasons. First, war affects large populations globally:
between 1989 and 2019, about one- sixth of the global
population have experienced war within their country
of residence.5 6 Second, absolute numbers add clarity
to the scope of war- related mental health burdens and,
as such, inform policy making, healthcare and research
beyond relative estimates. Third, countries with a recent
history of war are almost exclusively low/middle- income
countries (LMICs) with limited healthcare resources.7
Absolute estimates may reveal particular challenges for
mental healthcare in LMICs settings and inform tailored
approaches. All previous meta- analyses partly or exclu-
sively involved specific populations precluding extrapola-
tions to general war- surviving populations.
Against this background, we aimed to estimate the
absolute global number of war survivors with PTSD and/
or MD, as well as the absolute associated disease burden.
For this, we conducted a systematic literature search and
meta- analysis on high- quality epidemiological surveys
conducted in countries with a history of war within their
own territory between 1989 and 2019, and extrapolated
results to absolute numbers and the associated disability-
adjusted life years (DALYs) as a measure of disease
burden.
METHODS
Denition of war and war-aficted country
We used the definition of war and geo- referenced
war- data from the Uppsala Conflict Data Programme
(UCDP) from the Department of Peace and Conflict
Research of the Uppsala University.5 The UCDP supplies
geo- referenced war data from 1989 to 2019. Based on the
geo- referenced data, we classified war in four countries
(ie, India, Israel, Russia and Ukraine) as regional rather
than nationally distributed (see https:// ucdp. uu. se/)
which was relevant for the accuracy of extrapolations,
which are described in more detail elsewhere.6
Systematic literature search
Up until September 2017, we relied on our previous
systematic literature search with identical search strategy,2
which we pre- registered in the PROSPERO database (ID:
CRD42016032720; https://www. crd. york. ac. uk/ pros-
pero/ display_ record. php? RecordID= 32720). However,
for the present report, we excluded surveys that were not
representative of general populations. A new systematic
literature search was conducted in Medline, PsycINFO
and PTSDpubs between 1 August 2017 up until 15 January
2021 (see detailed search strategy in online supplemental
eList 1). We conducted the systematic review according
to the Preferred Reporting Items for Systematic Reviews
and Meta- Analyses (PRISMA) guidelines.8 Two authors
(THH, IV) independently conducted all search steps
(eg, duplicate detection, title and abstract screen, full-
text screen) as well as all following steps (eg, data extrac-
tion, risk of bias assessment); regular meetings between
three authors (THH, IV and NM) were held to discuss
disagreements. Inclusion and exclusion criteria were set
to maximise representativeness of general war surviving
populations and, therefore, to allow for extrapolations.
Epidemiological surveys were eligible if they met all of
the following inclusion criteria: (1) conducted after
the first year of war in a country with a history of war
between 1989 and 2019 as defined by the UCDP; (2)
using a random sampling technique to draw a represent-
ative sample from the general population; (3) including
at least 50 participants; (4) at least 80% of the partici-
pants were aged 18 years or older and (5) PTSD and/
or MD were measured with a (semi- )structured interview
based on the diagnostic criteria reported in any version
of the Diagnostic and Statistical Manual for Mental Disor-
ders (DSM) or the International Statistical Classification
of Diseases (ICD). There were no restrictions in terms
of language or population (other than the mentioned
inclusion criteria). In line with the inclusion criterion 2,
surveys were excluded if they were conducted in an area
with particularly high or low war intensity as compared
with the rest of the country, indicated by geo- referenced
UCDP data, or if surveys involved help- seeking popula-
tions. We also reviewed relevant secondary literature
(see PRISMA flow chart; figure 1)1 4 6 9 10 as well as refer-
ence lists of eligible articles. Since all relevant data were
reported in the eligible surveys, no contact with authors
of primary literature was necessary.
Coding of survey information
The main outcome was the point prevalence of PTSD,
MD and their comorbidity. We further extracted relevant
data for the planned moderator analyses (see later).
Quality assessment
We assessed the quality of included surveys with a scale
that we had developed previously.2 The scale is based on
the recommendations reported in the Strengthening
the Reporting of Observational Studies in Epidemiology
guidelines and related meta- analyses,11–13 and consists of
six quality items (see online supplemental eTable 1). Two
authors (THH, IV) independently rated the quality of
included trials on the applicable items with 73% agree-
ment. All disagreements were solved through discussions
between three authors (THH, IV and NM). A quality sum
score of percentage of the possible sum score was created
for each survey since they differed on the number of
applicable quality items.
Meta-analysis
We conducted random effects meta- analyses on Freeman-
Tukey double arcsine transformed prevalence propor-
tions using the inverse variance method.14 We used the
packages meta (V.4.16-2)15 and metafor (V.2.4-0)16 in R
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HoppenTH, etal. BMJ Global Health 2021;6:e006303. doi:10.1136/bmjgh-2021-006303 3
BMJ Global Health
(V.3.6.1).17 To calculate 95% CIs for individual studies
in the forest plots, we used the Agresti- Coull interval.18
Q- statistics and the I²-statistics were calculated to get an
estimate of homogeneity in effect sizes. The latter indi-
cates the degree of heterogeneity in percentages. We esti-
mated the between- study variance by calculating τ²-sta-
tistics via the restricted maximum likelihood method.19
To analyse the potential effects of outliers, we defined
outliers as prevalence proportions that were at least 3.3
SD above or below the pooled prevalence proportion
and aimed to supply outlier- adjusted results.20 To analyse
potential publication bias, we visually inspected funnel
plots and performed Egger’s test of asymmetry.21 As
recommended,22 we did this only in the presence of at
least 10 independent estimates. In case of detected asym-
metry, we used the trim and fill method, which supplies
asymmetry- adjusted results by introducing additional
hypothetical studies.23 To statistically control for effects
of potentially moderating variables (ie, total war deaths,
war deaths per 100.000 population, total conflict- related
deaths, conflict- related deaths per 100.000, war lengths
in years, years since end of war and conduct of survey,
response rate, quality of survey, mean age, % females, %
in a relationship, % in employment and continent) on
prevalence proportions, we planned to perform univar-
iate mixed- method meta- regressions if enough inde-
pendent surveys reported on the given information (ie,
k≥10).19 Data on country- specific war intensity, conflict
intensity and war length (accumulative for 1989–2019)
was retrieved from the UCDP (https:// ucdp. uu. se/).
Since there was more than one survey for some coun-
tries which experienced multiple wars (Rwanda, Kosovo,
Democratic Republic of the Congo, and Palestine for
PTSD; Rwanda and Kosovo for MD), we merged cases
and non- cases per country for these specific moderator
analyses. Some planned moderator analyses (interven-
tion utilisation, non- war- related trauma history) were
precluded since these variables were either not assessed
or assessed too heterogeneously (differences in defining
and assessing mean number of traumatic events per
trauma type, breadth of assessed trauma history) to allow
for the planned moderator analyses.
Population estimates, extrapolation and income groups
For all nationally distributed wars, we relied on popula-
tion estimates of the Population Division of the Depart-
ment of Economic and Social Affairs (DESA) of the
United Nations.24 Since people who were very young
during war might not be able to remember exposure
to war- related events,25 we only extrapolated data on
adults who were at least 6 years old at the time of the war.
Countries where only specific regions were affected by
war were: India (Punjab, Nagaland, Kashmir, Assam and
Manipur), Ukraine (Donetsk People’s Republik, Kharkiv
Oblast, Luhansk People’s Republic, Zaporizhzhia Oblast
and Dnipropetrovsk Oblast), Israel (Gaza strip and West
Bank) and Russia (Chechnya). For regional wars, we
relied on national consensus data and World Bank popu-
lation data since DESA does not supply age- grouped
regional population estimates. Definitions of LMICs
were based on the World Bank classifications (ie, gross
national income per capita of less than US$12 536).26
Disease burden estimate
To estimate the associated disease burden of the global
number of war survivors with PTSD and MD, we replied
on country- specific DALYs estimates published in the last
iteration of the Global Burden of Diseases (GBD) study;
the GBD 2019.27 Since the GBD 2019 does not report
on PTSD data separately, the estimate for all anxiety
disorders was used. Total country DALYs for PTSD and
all anxiety disorders were retrieved, divided by the total
country population and subsequently multiplied by the
retrieved number of adult war survivors.
RESULTS
Article synthesis
The PRISMA flowchart in figure 1 shows an overview of
the survey synthesis. Of the initial 3989 records identi-
fied, 74 full texts remained after the title and abstract
Figure 1 Preferred Reporting Items for Systematic Reviews
and Meta- Analyses owchart of study selection. MD, major
depression; PTSD, post- traumatic stress disorder.
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BMJ Global Health
screen for eligibility. After thorough screening of the 74
full texts, a total of 20 eligible publications were included
in the present meta- analysis reporting on 22 independent
surveys (N=15 420) for PTSD from 12 countries and 3
continents, 13 independent surveys (N=9836) for MD
from 9 countries and 3 continents, and 6 independent
surveys (N=1131) for PTSD and comorbid MD from 6
countries and 2 continents.
Characteristics of included studies
An overview of the characteristics of included surveys is
provided in table 1. On average, surveys assessed PTSD
and/or MD 6.88 years (weighted mean; SD=5.88) after
the end of warfare. War intensity and lengths varied
considerably across countries. Survey response rates were
high with a weighted mean of 88.91% (SD=11.10). Most
surveys used mental health professionals as interviewers
who were trained for the purpose of the survey. The most
frequently used interview measure was the Mini Inter-
national Neuropsychiatric Interview28 for both PTSD
and MD. Quality of surveys was moderate overall with a
weighted mean of 34.92% (SD=10.94) of the maximum
attainable quality sum scores. None of the included
surveys involved a formal psychometric validation of
translated measures.
Meta-analytic results
Prevalence of PTSD and MD
Figure 2 shows forest plots of prevalence of PTSD and
MD in the included surveys. Random effects models
yielded a pooled point prevalence of 26.51% (k=22,
95% CI 22.17 to 31.10) for PTSD. Heterogeneity was
large (I2=98%, Q=1057.13, p<0.001). No statistical
outliers were observed. The funnel plot (see online
supplemental eFigure 1) and Egger’s test of asymmetry
(t=0.77, p=0.453) did not indicate publication bias. For
MD, the random effects model yielded a pooled point
prevalence of 23.31% (k=13, 95% CI 18.55 to 28.42) with
large heterogeneity (I2=96.1%, Q=310.72, p<0.001). No
statistical outliers were observed. Again, the funnel plot
(see online supplemental eFigure 2) and Egger’s test
of asymmetry (t=0.77, p=0.457) did not indicate publi-
cation bias. For the comorbidity between PTSD and
MD, the random effects model yielded a pooled point
prevalence of 55.26% (k=6, 95% CI 42.11 to 68.05) with
large heterogeneity (I2=95.6%, Q=113.39, p<0.001; see
the corresponding forest plot in online supplemental
eFigure 3). No statistical outliers were observed. We used
pooled point prevalence in the extrapolation to absolute
numbers.
Moderator results
In the meta- regressions on prevalence of PTSD and MD,
none of the analysed potential moderators was found to
be significantly related (see online supplemental eTable
2). Meta- regressions for comorbidity point prevalence
were precluded (k<10).
Extrapolation to absolute numbers and DALYs
Table 2 shows point prevalence estimates for PTSD, MD
and their comorbidity per country as well as globally.
We estimate that a total of 854 653 860 adult war survi-
vors were alive in 2019 and resided in one of 43 coun-
tries which experienced at least one war between 1989
and 2019. Of these, 849 754 461 were residing in LMICs.
Based on the meta- analytic summary of epidemiological
surveys, the extrapolation yielded that, in 2019, about
227 million adult war survivors globally experienced
PTSD (95% CI 189 476 761 to 265 797 350) and about
199 million experienced MD (95% CI 158 538 291 to 242
892 627). Based on the meta- analytic results on comor-
bidity point prevalence, about 110 million (95% CI 83
891 464 to 135 569 084) adult war survivors globally
experienced comorbid PTSD and MD. Consequently,
about 315 699 683 adult war survivors globally expe-
rienced PTSD and/or MD in 2019 in 43 war- afflicted
countries. Of these, 313 889 900 were residing in LMICs.
Only two countries affected by war (Kuwait and Croatia)
were considered high- income. Extrapolations to disease
burden are also provided in table 2. When the GBD
2019 results are taken as a reference, the extrapolations
yielded 3 127 089 PTSD- associated DALYs and 4 114 663
MD- associated DALYs across 43 war- affected countries, of
which 3 105 387 (PTSD) and 4 083 950 (MD) were located
in LMICs.
DISCUSSION
Main ndings
We aimed to estimate the absolute global number of
war survivors with PTSD and/or MD and the associ-
ated disease burden in countries that experienced
warfare within their own territory between 1989 and
2019. Extrapolation informed by meta- analysis yielded
about 316 million adult survivors of war experiencing
PTSD and/or MD globally. Almost all war survivors of
recent wars reside in LMICs carrying a global accumu-
lated burden of 3 million PTSD- associated DALYs and 4
million MD- associated DALYs.
Strengths and limitation
We estimated the absolute global number of war survivors
with PTSD and/or MD by conducting an up- to- date and
comprehensive systematic literature search. We maxim-
ised validity of extrapolations by only including interview-
based epidemiological data from random general popu-
lation samples. The extrapolations to absolute numbers
may enable professionals from various disciplines to
better grasp the burden of PTSD and MD on survivors
of war and guide decision making to ultimately improve
mental health of survivors.
Our study also has several limitations. The meta-
analyses relied on only 41 surveys. This primarily reflects
the current state of literature on war survivors that has
mostly focused on refugees or other special war- surviving
populations rather than general populations.29 In fact,
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BMJ Global Health
Table 1 Characteristics of eligible epidemiological surveys included in the meta- analysis
Publication Country
Years
since
war*
War- related
deaths
1989–2019†
(per 100.000)
Conict- related
deaths 1989–
2019 ‡
Lengths
of war(s)
in years
1989–2019 N
Random
sampling
technique used
Response
rate in %
PTSD
assessment
MD
assessment
Expertise and
training of
interviewers
Quality of
survey in
%§
Ayazi et al53 Sudan 5 51 837
(118.22)
93 133 20 1200 Multistage
random cluster
sampling
95 NA MINI Local health
personnel, 9 days
of training
41.67
Canetti et al54 Palestine 0 1708 (33.48) 1710 1 1196 Stratied
3- stage cluster
random
sampling
62.9 PSS- I NA Trained
interviewers
not otherwise
specied
25.00
de Jong et al55 Algeria 6 18 920
(43.15)
21 153 6 653 Random sample
of population
based on
governmental
registries
76.7 CIDI NA n.r. 25.00
Palestine 0 s.a. s.a. s.a. 585 4- stage random
sampling
strategy
98 CIDI NA n.r. 33.33
Eytan et al56 Kosovo 2 1898 (106.10) 2847 2 996 Random
sampling
from eight
municipalities
93 MINI NA Local
psychosocial
counsellors,
trained by
authors
41.67
Fodor et al57 Rwanda 17 6749 (52.11) 516 805 1 465 Probability
proportional to
size sampling
based on
census data
96 NA MINI Experienced
Rwandan college
graduates,
1 week of training
50.00
Johnson et al58 Liberia 4 3048 (60.26) 23 245 1 1661 Combination
of systematic
random
sampling and
40×40 cluster
sampling
98.2 PSS- I NA Liberian public
health graduates
and community
health workers,
several days of
training
41.67
Johnson et al59 DRC 0 28 637
(31.97)
114 888 7 989 Systematic
cluster sampling
strategy
98.9 PSS- I NA Experienced
Congolese
interviewers,
several days of
training
58.33
Madianos et al60 Palestine 0 s.a. s.a. s.a. 916 Multistage
sample in four
areas of West
Bank
92 SCID SCID Second author
(native to West
Bank), training
through pilot
interviews
50.00
Continued
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BMJ Global Health
Publication Country
Years
since
war*
War- related
deaths
1989–2019†
(per 100.000)
Conict- related
deaths 1989–
2019 ‡
Lengths
of war(s)
in years
1989–2019 N
Random
sampling
technique used
Response
rate in %
PTSD
assessment
MD
assessment
Expertise and
training of
interviewers
Quality of
survey in
%§
Morina and Ford61 Kosovo 6 s.a. s.a. s.a. 102 Random sample
of civilians,
random walk
technique
81 MINI MINI Psychology
students trained
by the rst author
25.00
Morina et al62 Kosovo 6 s.a. s.a. s.a. 84 Random walk
technique in the
region of Drenica
90 MINI NA Psychology
students trained
by the rst author
41.67
Morina et al63 Kosovo 8 s.a. s.a. s.a. 163 Random walk
technique in
different regions
90.1 MINI MINI Psychology
students trained
by the rst author
31.25
Mugisha et al64 Uganda 7 9970 (21.80) 17 034 3 2361 Multistage
sampling,
random
selection
of parishes
from selected
subcounties
n.r. MINI MINI Psychiatric
nurses trained for
this study
18.75
Munyandamutsa
et al65
Rwanda 14 s.a. s.a. s.a. 962 Multistage
random
sampling
procedure
n.r. MINI MINI Psychologists,
social workers
and physicians,
20 hours of
training
18.75
Priebe et al66 Croatia 13 3091 (31.98) 1478 1 727 Multistage
probabilistic
sampling frame
and random-
walk technique
70 MINI MINI Trained
mental health
professionals or
trainees
31.25
Kosovo 8 s.a. s.a. s.a. 648 Multistage
probabilistic
sampling frame
and random-
walk technique
91 MINI MINI Trained
mental health
professionals or
trainees
43.75
Serbia 13 5806 (66.45) 7267 3 637 Multistage
probabilistic
sampling frame
and random-
walk technique
70.1 MINI MINI Trained
mental health
professionals or
trainees
31.25
Bosnia and Herze-
govina
13 13 440
(409.65)
26 333 4 640 Multistage
probabilistic
sampling frame
and random-
walk technique
85 MINI MINI Trained
mental health
professionals or
trainees
43.75
Table 1 Continued
Continued
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BMJ Global Health
Publication Country
Years
since
war*
War- related
deaths
1989–2019†
(per 100.000)
Conict- related
deaths 1989–
2019 ‡
Lengths
of war(s)
in years
1989–2019 N
Random
sampling
technique used
Response
rate in %
PTSD
assessment
MD
assessment
Expertise and
training of
interviewers
Quality of
survey in
%§
Rieder et al67 Rwanda 16 s.a. s.a. s.a. 172 Random
sampling in
Muhanga district
n.r. PSS- I NA Experienced local
bachelor- level
psychologists
16.67
Rugema et al68 Rwanda 17 s.a. s.a. s.a. 917 Two- stage
random
sampling
99.8 MINI MINI Experienced
clinical
psychologists,
several days of
training
31.25
Schaal et al69 ** Rwanda 15 s.a. s.a. s.a. 112 Random
community
sample of Butare
and Kigali
97 PSS- I NA Masters- level
and clinical
psychologists,
extensive
previous training
41.67
Somasundaram and
Sivayokan70
Sri Lanka 4 61 265
(286.11)
65 628 15 98 Random
sampling
procedure in a
suburb of Jaffna
97 SIQ SIQ Trained medical
students
31.25
Veling et al71 DRC 0 s.a. s.a. s.a. 93 Balanced
sampling to
12 quarters of
Bunia
n.r. CIDI NA Trained local
interviewers
25.00
Yasan et al72 Turkey 9.8 26 981
(31.99)
28 611 9 708 Random
sampling of
regions in
Diyarbakir,
proportionate
sample of
residents
98.3 CAPS NA Final- year
psychology
students trained
by psychiatry
professors
41.67
Summary (ie, sum or
weighted/unweighted
mean (SD) or most
prevalent option)
12
countries+Palestine
from 3 continents
6.88
(5.88)
Total: 17 813
(18 807)¶
Per 100.000:
99.48
(112.16)
70 779 (133,300)¶ 3.92 (4.83)¶ 17 085 (Multistage)
random
sampling
procedure
88.91
(11.10)
MINI MINI Mental health
professionals
with specic
training for the
used interview
34.92
(10.94)
*Timespan in years between the end of war and the time the respective survey was conducted.
†Number of war- related death (ie, state- based violence) in the respective country with a history of war between 1989 and 2019 as dened by Uppsala Conict Data Programme (UCDP).5 Retrieved from: https://ucdp.uu.se/.
‡Number of all conict- related death (ie, state- based violence+non- state violence+one- sided violence) in the respective country with a history of war between 1989 and 2019 as dened by the UCDP.
§As assessed with Strengthening the Reporting of Observational Studies in Epidemiology criteria.11
¶To calculate these unweighted means and SDs, country- specic data were considered once per country.
**Only representative sample included.
CAPS, Clinician- Administered PTSD Scale; CIDI, Composite International Diagnostic Interview; DRC, Democratic Republic of Congo; MD assessment, used (semi- )structured interview based on Diagnostic and Statistical
Manual of Mental Disorders (DSM) or International Statistical Classication of Diseases (ICD) diagnostic criteria to assess major depression; MINI, Mini International Neuropsychiatric Interview; n, included amount of
subjects in the given survey; NA, not applicable; n.r., not reported; PSS- I, Post- traumatic Symptom Scale Interview; PTSD assessment, used (semi- )structured interview based on Diagnostic and Statistical Manual of Mental
Disorders (DSM) or International Statistical Classication of Diseases (ICD) diagnostic criteria to assess post- traumatic stress disorder; s.a., see intensity/lengths of war for the respective country above; SCID, Structured
Clinical Interview for DSM- IV; SIQ, Stress Impact Questionnaire.
Table 1 Continued
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8HoppenTH, etal. BMJ Global Health 2021;6:e006303. doi:10.1136/bmjgh-2021-006303
BMJ Global Health
the current literature base on interview- based randomly
sampled surveys covers only 12 countries (and Palestine)
and for the remaining 30 war- affected countries such
samples are currently lacking. Therefore, our summary
of the available literature might not be generalisable to
countries with lacking data. On the notion of generalis-
ability to countries with lacking data, it is worthwhile to
check whether countries with available data may differ
from countries without such data in terms of war- intensity.
As can be seen in table 1, countries with available data
bewailed on average 17 813 war- related deaths from
1989 to 2019 (SD=18 807) which translates into 99.48
war- related deaths per 100.000 population (SD=112.16).
Whereas countries with missing data on average bewailed
40 042 (SD=71 980) or 183.17 per 100.000 population
(SD=339.65). Across all 43 war- afflicted countries, an
average of 33 322 (SD=61 593) individuals or 155.97 per
100.000 (SD=288.95) died due to war events. This demon-
strates that the war- afflicted countries with available data
are somewhat below average in terms of war- intensity.
The performed moderator analyses did not yield signifi-
cant differences in prevalence rates across 12 war- affected
countries (plus Palestine) despite varying degrees of war-
intensity and war- length (see online supplemental eTable
2). This finding may be unexpected, since higher inten-
sity of trauma has been shown to relate to higher risk and
prevalences of PTSD generally30 and also in the context
of war trauma31 and genocide such as the Holocaust.32
Therefore, the results of this moderator analysis should
be interpreted with caution as a dose–response relation-
ship between war intensity and prevalences of trauma-
related disorders appears plausible.31
Also related to the issue of limited data and generalis-
ability, extrapolative accuracy is naturally restrained. Due
Figure 2 Forest plots for point prevalence of post- traumatic stress disorder (top) and major depression (bottom).
Medizin. Protected by copyright. on July 28, 2021 at Univ.- & Landesbibliothek, Zweigbibliothekhttp://gh.bmj.com/BMJ Glob Health: first published as 10.1136/bmjgh-2021-006303 on 28 July 2021. Downloaded from
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BMJ Global Health
Table 2 Extrapolation to absolute prevalence and associated disease burden, as measured by DALYs
Country
Last war-
affected
year for the
given country
(1989–2019)
Total
population
of adult war
survivors (2019)
Absolute prevalence of war survivors with
PTSD (95% CI)
PTSD-
associated
DALYs
Absolute prevalence of war survivors
with MD (95% CI)
MD-
associated
DALYs
Absolute prevalence of war survivors
with PTSD+MD
El Salvador 1989 2 483 500 658 376 (550 592 to 772 369) 10,262 578 904 (460 689 to 705 811) 12 636 319 902 (243 776 to 393 944)
Mozambique 1991 6 686 071 1 772 477 (1 482 302 to 2 079 368) 20 387 1 558 523 (1 240 266 to 1 900 181) 30 377 861 240 (656 294 to 1 060 575)
Kuwait 1991 2 317 732 614 431 (513 841 to 720 815)11 450 540 263 (429 939 to 658 699)16 877 298 550 (227 505 to 367 649)
Croatia 1991 2 581 667 684 400 (572 356 to 802 898)10 251 601 787 (478 899 to 733 710)13 836 332 547 (253 412 to 409 516)
Myanmar 1992 22 181 071 5 880 202 (4 917 543 to 6 898 313) 86 017 5 170 408 (4 114 589 to 6 303 860) 36 527 2 857 167 (2 177 259 to 3 518 462)
Peru 1992 14 322 678 3 796 942 (3 175 338 to 4 454 353) 80 362 3 338 616 (2 656 857 to 4 070 505) 39 573 1 844 919 (1 405 891 to 2 271 928)
Georgia 1993 2 464 257 653 275 (546 326 to 766 384) 5 733 574 418 (457 120 to 700 342) 12 726 317 424 (241 888 to 390 892)
Azerbaijan 1994 5 508 694 1 460 355 (1 221 277 to 1 713 204) 13 963 1 284 077 (1 021 863 to 1 565 571) 19 722 709 581 (540 725 to 873 814)
Bosnia-
Herzegovina
1995 2 236 056 592 778 (495 734 to 695 413) 8 519 521 225 (414 788 to 635 487) 9 678 288 029 (219 488 to 354 693)
Tajikistan 1996 3 523 143 933 985 (781 081 to 1 095 697) 7757 821 245 (653 543 to 1 001 277) 10 380 453 820 (345 826 to 558 857)
Congo 1998 2 191 526 580 974 (485 861 to 681 565) 7030 510 845 (406 528 to 622 832) 15,489 282 293 (215 117 to 347 630)
Serbia 1999 6 352 650 1 684 088 (1 408 383 to 1 975 674) 22 395 1 480 803 (1 178 417 to 1 805 423) 28 139 818 292 (623 566 to 1 007 686)
Algeria 1999 24 441 969 6 479 566 (5 418 785 to 7 601 452) 108 133 5 697 423 (4 533 985 to 6 946 408) 147 708 3 148 396 (2 399 185 to 3 877 096)
Sierra Leone 1999 3 129 883 829 732 (693 895 to 973 394) 10 829 729 576 (580 593 to 889 513) 15 341 403 164 (307 224 to 496 476)
Kosovo 1999 915 361 242 662 (202 936 to 284 677) NA 213 371 (169 799 to 260 146) NA 117 909 (89 850 to 145 199)
Ethiopia 2000 44 350 185 11 757 234 (9 832 436 to 13 792 908) 121 905 10 338 028 (8 226 959 to 12,604,323) 194 816 5 712 794 (4 353 344 to 7 035 028)
Eritrea 2000 1 428 785 378 771 (316 763 to 444 352) 8 864 333 050 (265 040 to 406 061) 14 143 184 043 (140 247 to 226 640)
Angola 2001 11 202 755 2 969 850 (2 483 651 to 3 484 057) 33 302 2 611 362 (2 078 111 to 3 183 823) 68 513 1 443 039 (1 099 645 to 1 777 032)
Burundi 2002 5 293 042 1 403 185 (1 173 467 to 1 646 136) 15 802 1 233 808 (981 859 to 1 504 283) 24 527 681 802 (519 557 to 839 606)
Liberia 2003 2 463 836 653 163 (546 232 to 766 253) 7550 574 320 (457 042 to 700 222) 11 837 317 369 (241 846 to 390 825)
Uganda 2004 19 435 624 5 152 384 (4 308 878 to 6 044 479) 57 787 4 530 444 (3 605 308 to 5 523 604) 122 373 2 503 523 (1 907 770 to 3 082 967)
Russia
(regional)
2004 959 727 254 424 (212 771 to 298 475) 3091 223 712 (178 029 to 272 754) 4,676 123 623 (94 205 to 152 236)
India (regional) 2005 53 366 769 14 147 530 (11 831 413 to 16 597 065) 152 752 12 439 794 (9 899 536 to 15 166 836) 265 286 6 874 230 (5 238 397 to 8 465 280)
Colombia 2005 35 348 853 9 370 981 (7 836 841 to 10 993 493) 156 309 8 239 818 (6 557 212 to 10 046 144) 102 122 4 553 323 (3 469 787 to 5 607 196)
Nepal 2005 17 553 695 4 653 485 (3 891 654 to 5 459 199) 55 365 4 091 766 (3 256 210 to 4 988 760) 125 913 2 261 110 (1 723 043 to 2 784 447)
Chad 2006 6 934 582 1 838 358 (1 537 397 to 2 156 655) 19 251 1 616 451 (1 286 365 to 1 970 808) 33 647 893 251 (680 688 to 1 099 995)
Rwanda 2009 7 004 398 1 856 866 (1 552 875 to 2 178 368) 22 281 1 632 725 (1 299 316 to 1 990 650) 40 235 902 244 (687 541 to 1 111 069)
Sri Lanka 2009 15 326 238 4 062 986 (3 397 827 to 4 766 460) 63 630 3 572 546 (2 843 017 to 4 355 717) 50 174 1 974 189 (1 504 399 to 2 431 118)
Israel (regional) 2014 5 840 055 1 548 199 (1 294 740 to 1 816 257) 22 332 1 361 317 (1 083 330 to 1 659 744) 39 874 752 264 (573 251 to 926,376)
South Sudan 2014 5 828 199 1 545 056 (1 292 112 to 1 812 570) 19 525 1 358 553 (1 081 131 to 1 656 374) 22 909 750 736 (572 087 to 924 495)
Pakistan 2015 130 645 594 34 634 147 (28 964 128 to 40 630 780) 382 665 30 453 488 (24 234 758 to 37 129 478) 581 982 16 828 597 (12 823 964 to 20 723 599)
Continued
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10 HoppenTH, etal. BMJ Global Health 2021;6:e006303. doi:10.1136/bmjgh-2021-006303
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Country
Last war-
affected
year for the
given country
(1989–2019)
Total
population
of adult war
survivors (2019)
Absolute prevalence of war survivors with
PTSD (95% CI)
PTSD-
associated
DALYs
Absolute prevalence of war survivors
with MD (95% CI)
MD-
associated
DALYs
Absolute prevalence of war survivors
with PTSD+MD
Ukraine
(regional)
2015 9 172 307 2 431 579 (2 033 500 to 2 852 587) 30 410 2 138 065 (1 701 463 to 2 606 770) 68 580 1 181 495 (900 339 to 1 454 953)
Sudan 2016 23 446 328 6 215 622 (5 198 051 to 7 291 808) 98 386 5 465 339 (4 349 294 6 663 446) 132 072 3 020 146 (2 301 454 to 3 719 163)
Turkey 2016 60 057 715 15 921 300 (13 314 795 to 18 677 949) 267 749 13 999 453 (11 140 706 to 17 068 403) 378 125 7 736 098 (5 895 170 to 9 526 628)
Iraq 2017 70 339 201 18 646 922 (15 594 201 to 21 875 492) 384 721 16 396 068 (13 047 922 to 19 990 401) 409 203 9 060 467 (6 904 384 to 11 157 524)
Philippines 2017 42 632 563 11 301 892 (9 451 639 to 13 258 727) 184 410 9 937 650 (7 908 340 to 12 116 174) 121 384 5 491 546 (4 184 745 to 6 762 571)
DR Congo 2018 22 520 461 5 970 174 (4 992 786 to 7 003 863) 71 413 5 249 519 (4 177 546 to 6 400 315) 144 335 2 900 884 (2 210 573 to 3 572 298)
Afghanistan 2019 19 791 367 5 246 691 (4 387 746 to 6 155 115) 83 888 4 613 368 (3 671 299 to 5 624 707) 119 476 2 549 347 (1 942 689 to 3 139 397)
Somalia 2019 7 433 691 1 970 671 (1 648 049 to 2 311 878) 24 977 1 732 793 (1 378 950 to 2 112 655) 43 406 957 542 (729 679 to 1 179 166)
Yemen 2019 16 284 148 4 316 928 (3 610 196 to 5 064 370) 76 436 3 795 835 (3 020 709 to 4 627 955) 113 562 2 097 578 (1 598 426 to 2 583 066)
Libya 2019 4 619 825 1 224 716 (1 024 215 to 1 436 766) 24 878 1 076 881 (856 978 to 1 312 954) 34 089 595 085 (453 475 to 732 818)
Syria 2019 11 163 348 2 959 404 (2 474 914 to 3 471 801) 51 859 2 602 176 (2 070 801 to 3 172 624) 58 620 1 437 963 (1 095 776 to 1 770 781)
Nigeria 2019 102 874 311 27 271 980 (22 807 235 to 31 993 911) 282 463 23 980 002 (19 083 185 to 29 236 879) 379 778 13 251 349 (10 097 979 to 16 318 391)
Total n.a. 854 653 860 226 568 738 (189 476 761 to 265 797 350) 3 127 089 199 219 815(158 538 291 to 242 892 627) 4 114 663 110 088 870 (83 891 464 to 135 569 084)
LMICs only
total
n.a. 849 754 461 225 269 908 (188 390 564 to 264 273 637) 3 105 387 198 077 765 (157 629 453 to 241 500 218) 4 083 950 109 457 773 (83 410 547 to 134 791 919)
Bold indicates that the respective war- affected country is a high- income country.
DALYs, disability- adjusted life years; LB, lower bound; MD, major depression; NA, data on Kosovo not available; n.a., not applicable; PTSD, post- traumatic stress disorder; UB, upper bound.
Table 2 Continued
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BMJ Global Health
to the general scarcity of data, we had to rely on pooled
prevalences of PTSD and MD for extrapolations. In the
light of varying degrees of war intensity and lengths as
well as more general country- specific differences, such
an approach is limited. However, the CIs for the pooled
PTSD and MD prevalences were fairly narrow (22.17%
to 31.10% and 18.55% to 28.42%, respectively) indi-
cating fairly similar prevalences of PTSD and MD across
the included surveys from 12 war- affected countries (plus
Palestine) from three continents. Similarly, the moder-
ator analysis on pooled prevalences by continent did not
yield significant differences in PTSD prevalences across
the three war- afflicted continents (ie, Africa, Asia and
Europe). Surveys on MD were too scarce to allow for
this moderator analysis. As more data accumulates, more
fine- grained meta- analyses and, consequently, more fine-
grained extrapolations will become possible.
Another potential limitation is that the current liter-
ature base exclusively covers cross- sectional surveys and
lacks longitudinal data on remission from PTSD and MD.
In their summary of the World Mental Health (WMH)
Surveys, Kessler et al reported that remission of war-
related PTSD would steeply increase about 6 years after
exposure. The remission rate was reported to rise from
about 20% at 5 years after war to about 70% at 6 years
after war.33 In our review, the mean time between war and
the assessment of disorders across all included surveys
was 6.88 years. In our moderator analyses (see online
supplemental eTable 2), the number of years between
the end of the (last) war and the conduct of the survey
was not found to be related to prevalence rates. This
finding is at odds with previous research as illustrated by
the above- mentioned summary of the WMH surveys. Yet,
several factors might explain why remission rates may be
dampened in post- war settings. Besides war- trauma, non-
war- related traumatic experiences and difficult socioeco-
nomic conditions may also influence the development
and maintenance of PTSD and MD.34 35 Socioeconomic
risk factors are more prevalent in LMICs with a history
of war as compared with the countries included in the
WHM surveys which were mostly high- income countries.
Furthermore, individuals with mental disorders in LMICs
are less likely to receive appropriate healthcare,36–38 and
PTSD as well as MD, if left untreated, may follow a chronic
course.39 40 However, while remission rates post- conflict
might be dampened in war- ridden LMICs for various
reasons, a degree of remission is still to be expected
particularly over several decades as illustrated by long-
term epidemiological data on WWII survivors.41–43 There-
fore, null findings more probably boil down to a lack of
longer- term data rather than lacking remissions per se.
Another potential limitation concerns heterogeneity
in outcomes based on different nosology. We included
surveys that conducted diagnostic interviews based on
any ICD or DSM iteration, which use different criteria for
defining PTSD and MD. Finally, this study estimates the
disease burden for PTSD. Since the GBD 2019 does not
report on PTSD DALYs separately, all anxiety disorder
DALYs had to be used. The presented estimate, therefore,
may overestimate or underestimate the PTSD- associated
DALYs. The GBD study has already announced that it
will report data on PTSD separately in coming iterations,
which will allow for more accurate extrapolations.
Comparison with the literature
The pooled PTSD and MD prevalences are slightly
lower than reported prevalences in most meta- analyses
on these conditions in war- surviving populations (ie,
≥30%).3 4 29 In our previous meta- analyses, we found
similarly high prevalences (ie, 24%–26% for PTSD and
23%–27% for MD).2 6 However, recent estimates by the
WHO are considerably lower with 15.3% for PTSD and
10.8% for MD.1 As mentioned before, all previous meta-
analyses partly or exclusively involved specific popula-
tions (eg, refugees, bereaved individuals) and precluded
extrapolations to general war- surviving. Furthermore,
related meta- analyses included self- report- based data.1
Self- report- based measures of PTSD (eg, PTSD CheckList
– Civilian Version) and MD (eg, Patient Health Question-
naire – 9) either are not validated for LMICs or have poor
psychometric properties in LMICs.44 To our knowledge,
we performed the first meta- analysis that exclusively
included representative interview- based data and, there-
fore, allowed for more valid extrapolations. We aimed at
estimating the absolute prevalence and disease burden
of PTSD and MD in war- afflicted countries, irrespective
of assumptions about their aetiology. The elevated prev-
alences of PTSD and MD in war- surviving populations
are not to be mistaken as solely caused by war- related
trauma. The aetiologies of PTSD and MD are complex
and, besides war experiences, non- war- related traumatic
experiences, psychological stressors and aversive social
conditions can play a role in the development and main-
tenance of PTSD and MD. However, independently of
the precise aetiology of the disorders, the reported preva-
lences reflect the extent of the total burden and the need
for help due to PTSD and MD in war- surviving popula-
tions.
Clinical, policy and research implications
In theory, effective psychological interventions for
both youth and adult survivors of mass conflict do
exist.38 45 However, most LMICs lack the resources in
terms of both funding and qualified staff to provide
evidence- based psychological treatments for all affected
war survivors.36 37 46 While the allocation of financial and
human resources for mental healthcare should surely
increase,36 47 other approaches than specialised treat-
ments are needed to address the mental health needs of
survivors of war. For this, mental healthcare should be
as much as possible integrated into the overall response
to healthcare following wars. This may include strength-
ening of primary care to address mental disorders in
primary care, task- sharing of psychosocial interventions
with trained non- professional individuals, involving
families and informal carers, using digital platforms to
Medizin. Protected by copyright. on July 28, 2021 at Univ.- & Landesbibliothek, Zweigbibliothekhttp://gh.bmj.com/BMJ Glob Health: first published as 10.1136/bmjgh-2021-006303 on 28 July 2021. Downloaded from
12 HoppenTH, etal. BMJ Global Health 2021;6:e006303. doi:10.1136/bmjgh-2021-006303
BMJ Global Health
facilitate the delivery of interventions, and the develop-
ment and implementation of community- based inter-
ventions.48–52 All these options may benefit from more
systematic research to inform public health policies and
practice.
CONCLUSIONS
The effects of exposure to war place a large mental health
burden on the affected countries. An extrapolation from
relative prevalence of PTSD and MD to absolute numbers
suggests that hundreds of millions adult war survivors
globally are affected. Countries with a recent history of
war are almost exclusively LMICs. These countries lack
the resources to provide specialised treatments for most
of the affected war survivors. Therefore, alternative strat-
egies—such as low- cost and technology- based interven-
tions that build on existing resources—should be brought
forward to meet the high burden of war- related mental
disorders. The presented results generally illustrate the
importance of peace- building and maintenance.
Twitter Thole H Hoppen @HoppenDr
Contributors THH and NM designed the study. THH and IV conducted the
systematic literature search and data extraction. THH conducted the statistical
analyses. THH wrote the manuscript. NM, SP and IV commented on and contributed
to the manuscript.
Funding The authors have not declared a specic grant for this research from any
funding agency in the public, commercial or not- for- prot sectors.
Competing interests None declared.
Patient consent for publication Not required.
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement All data analysed in this meta- analysis and in the
extrapolations is published and publically available.
Supplemental material This content has been supplied by the author(s). It has
not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been
peer- reviewed. Any opinions or recommendations discussed are solely those
of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and
responsibility arising from any reliance placed on the content. Where the content
includes any translated material, BMJ does not warrant the accuracy and reliability
of the translations (including but not limited to local regulations, clinical guidelines,
terminology, drug names and drug dosages), and is not responsible for any error
and/or omissions arising from translation and adaptation or otherwise.
Open access This is an open access article distributed in accordance with the
Creative Commons Attribution Non Commercial (CC BY- NC 4.0) license, which
permits others to distribute, remix, adapt, build upon this work non- commercially,
and license their derivative works on different terms, provided the original work is
properly cited, appropriate credit is given, any changes made indicated, and the
use is non- commercial. See:http:// creativecommons. org/ licenses/ by- nc/ 4. 0/.
ORCID iD
Thole HHoppen http:// orcid. org/ 0000- 0002- 6050- 8696
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1
Supplemental content
eList 1. Search Strategy
eTable 1. Quality Assessment
eFigure 1. Funnel Plot – Meta-analysis on PTSD Point Prevalences
eFigure 2. Funnel Plot – Meta-analysis on MD Point Prevalences
eFigure 3. Forest Plot – Meta-analysis on Comorbidity Point Prevalences (PTSD + MD)
eTable 2. Moderator Results
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Supplemental material placed on this supplemental material which has been supplied by the author(s) BMJ Global Health
doi: 10.1136/bmjgh-2021-006303:e006303. 6 2021;BMJ Global Health, et al. Hoppen TH
2
eList 1. Search Strategy
1) Depression (TI depress* OR AB depress* OR SU depress*) OR (TI MDD OR AB
MDD OR SU MDD)
2) PTSD (TI posttraumatic stress OR AB posttraumatic stress OR SU posttraumatic
stress) OR (TI post-traumatic stress OR AB post-traumatic stress OR SU post-traumatic
stress) OR (TI posttraumatic syndrome* OR AB posttraumatic syndrome* OR SU
posttraumatic syndrome*) OR (TI post-traumatic syndrome* OR AB post-traumatic
syndrome* OR SU post-traumatic syndrome*) OR (TI PTSD OR AB PTSD OR SU
PTSD)
3) General mental health (TI mental health OR AB mental health OR SU mental
health) OR (TI mental disorders OR AB mental disorders OR SU mental disorders)
4) War survivors (TI genocide OR AB genocide OR SU genocide ) OR ( TI holocaust
OR AB holocaust OR SU holocaust) OR (TI war* OR AB war* OR SU war*) OR (TI
mass conflict* OR AB mass conflict* OR SU mass conflict*) OR (TI post-conflict*
OR AB post-conflict* OR SU post-conflict*) OR (TI political conflict* OR AB political
conflict* OR SU political conflict*) OR (TI armed conflict* OR AB armed conflict*
OR SU armed conflict*) OR (TI terrorism OR AB terrorism OR SU terrorism) OR (TI
torture OR AB torture OR SU torture) OR (TI persecution OR AB persecution OR SU
persecution) OR (TI civilian* OR AB civilian* OR SU civilian*) OR (TI ethnic
cleansing OR AB ethnic cleansing OR SU ethnic cleansing)
Combined search (TI OR AB OR SU): 1 OR 2 OR 3 AND 4
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Supplemental material placed on this supplemental material which has been supplied by the author(s) BMJ Global Health
doi: 10.1136/bmjgh-2021-006303:e006303. 6 2021;BMJ Global Health, et al. Hoppen TH
3
eTable 1. Quality Assessment
Bias type
High quality (score=2)
Moderate quality (score=1)
Poor quality (score=0)
1. Selection (sample
population)
Random or probability sampling
Special population (all shared something in common, e.g. torture)
Mixed sampling (convenience sampling, snowballing, advertisement, non-
randomized etc.)
Sample selection ambiguous and sample
unlikely to be representative.
2. Selection (participation rate)
High response rate (>85%).
Moderate response rate (70–85%).
Low response rate (<70%) or not reported
3a. Reported psychometric quality
of PTSD measurement:
language in which it is used in this
study
High (good results on validity and reliability
reported)
Medium (only reliability data provided, yet no data on validity; or psychometric data
are in the medium range, e.g., reliability lower than 0.70)
No report, or
Low (e.g., only internal consistency reported; or
general statement that psychometrics are good)
4a. Reported psychometric quality
of PTSD measurement:
for original version of instrument if
in different language (e.g. English)
High (good results on validity and reliability
reported)
Medium (only reliability data provided, yet no data on validity; or psychometric data
are in the medium range, e.g., reliability lower than 0.70)
No report, or
Low (e.g., only internal consistency reported; or
general statement that psychometrics are good)
3b. Reported psychometric quality
of MD measurement:
language in which it is used in this
study
High (good results on validity and reliability
reported)
Medium (only reliability data provided, yet no data on validity; or psychometric data
are in the medium range, e.g., reliability lower than 0.70)
No report, or
Low (e.g., only internal consistency reported; or
general statement that psychometrics are good)
4b. Reported psychometric quality
of MD measurement:
for original version of instrument if
in different language (e.g. English)
High (good results on validity and reliability
reported)
Medium (only reliability data provided, yet no data on validity; or psychometric data
are in the medium range, e.g., reliability lower than 0.70)
No report, or
Low (e.g., only internal consistency reported; or
general statement that psychometrics are good)
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance
Supplemental material placed on this supplemental material which has been supplied by the author(s) BMJ Global Health
doi: 10.1136/bmjgh-2021-006303:e006303. 6 2021;BMJ Global Health, et al. Hoppen TH
4
5. Training in the use of the
psychiatric interview
High quality in training:
interviewers were extensively trained by
experienced professionals while applying the
interview in question with potential study
participants
Moderate quality in training:
interviewers were trained by experienced professionals but no interview sessions
with potential study participants were applied or reported
Low quality in training:
No training was used or reported
6. Interrater-reliability (IRR)
High IRR (>85%).
Moderate IRR (70–85%).
No IRR reported, or
Low IRR (<70%).
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance
Supplemental material placed on this supplemental material which has been supplied by the author(s) BMJ Global Health
doi: 10.1136/bmjgh-2021-006303:e006303. 6 2021;BMJ Global Health, et al. Hoppen TH
5
eFigure 1. Funnel Plot – Meta-analysis on PTSD Point Prevalences
eFigure 2. Funnel Plot – Meta-analysis on MD Point Prevalences
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance
Supplemental material placed on this supplemental material which has been supplied by the author(s) BMJ Global Health
doi: 10.1136/bmjgh-2021-006303:e006303. 6 2021;BMJ Global Health, et al. Hoppen TH
6
eFigure 3. Forest Plot – Meta-analysis on Comorbidity Point Prevalences (PTSD + MD)
eTable 2. Moderator Results
Analyzed potential moderator
k
Q
p
PTSD
total war-related deaths 1989-2019
12
0.36
.548
total war-related deaths 1989-2019 (per 100.000)
12
0.71
.401
any conflict-related deaths 1989-2019
12
0.00
.972
any conflict-related deaths 1989-2019 (per 100.000)
12
0.01
.917
lengths of war(s) in years
12
0.15
.702
years between end of (last) war and conduct of survey
22
0.96
.326
response rate of survey
18
0.53
.468
quality of survey
22
3.33
.068
mean age of sample
19
2.07
.150
proportion of female participants
22
0.37
.544
proportion of participants in a relationship
16
0.29
.588
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance
Supplemental material placed on this supplemental material which has been supplied by the author(s) BMJ Global Health
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7
proportion of participants in employment
11
0.69
.406
continent (with Africa as the reference category)
22
2.87
.238
MD
total war-related deaths 1989-2019
9a
0.05
.823
total war-related deaths 1989-2019 (per 100.000)
9a
0.62
.430
any conflict-related deaths 1989-2019
9a
0.01
.928
any conflict-related deaths 1989-2019 (per 100.000)
9a
0.00
.997
lengths of war(s) in years
9a
0.10
.751
years between end of (last) war and conduct of survey
13
0.12
.725
response rate of survey
11
0.02
.879
quality of survey
13
1.87
.171
mean age of sample
11
0.01
.920
proportion of female participants
13
1.39
.238
proportion of participants in a relationship
12
2.38
.123
proportion of participants in employment
10
0.77
.380
continent (with Africa as the reference category)
n.a. (k < 4 per category)
Note: n.a. = not applicable.
aNote that moderator analyses were performed despite k < 10 since surveys from Kosovo and Rwanda
had to be merged per country (as described in the main text in more detail).
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance
Supplemental material placed on this supplemental material which has been supplied by the author(s) BMJ Global Health
doi: 10.1136/bmjgh-2021-006303:e006303. 6 2021;BMJ Global Health, et al. Hoppen TH