Table 3.

Literature included in the review

Study	Study design, target population, sample size (n = ) and intervention	Mechanism							Outcomes
		Mental health literacy	Cultural competency	Strong therapeutic relationship	Safe spaces	Empowerment	Gender matching	Social connection
(Abdulah and Abdulla, 2020)	Pre and post-test quasi-experimental study of art therapy delivered to Yazidis (females, aged 10–27) in Sharya camp, KRI (n = 14)								Decline in suicidal ideation score (16.71 → 6.50, p=0.002) Increased desire to live (0.86 → 1.93, p<0.0001) Passive/active suicide attempts stopped (p=0.012 and p=0.005)
(Acarturk et al., 2016)	Randomised control trial (RCT) of EMDR delivered to adults (males and females, aged ≥18) in Kilis Refugee Camp at the Turkish–Syrian border, Turkey (n = 70)*								Depression in intervention v. control group immediately post-treatment (10.45 v. 26.35, p<0.001) and at 1 month followup (12.85 v. 26.13, p<0.001) PTSD diagnosis in intervention v. control immediately post intervention: 39% v. 94%; 5 week follow-up: 51% v. 96%
(Atulomah et al., 2020)	Case-control study of motivational counselling delivered to IDPs (males and females, aged ≥60) living in 2 IDP camps, Borno State Nigeria (n = 40)								PTSD declined in intervention v. control group (3.50 → 2.60 v. 3.75 → 3.75 p<0.05). At 13 week follow-up: intervention group had higher PTSD symptom reduction than control group
(Bass et al., 2016)	RCT of trauma counselling and psychoeducation delivered to IDPs (males and females, aged ≥18) living in Dohuk governorate, KRI (n = 209)								Significant improvements in depression in intervention v. control group (pre-post change −0.83 v. −0.62, p=0.02), functional impairment (-0.76 v. -0.39, p=0.03) and anxiety (−0.64 v. -0.19, p=0.01)
(Bolton et al., 2007)	RCT of group IPT v. creative play delivered to adolescents (males and females, aged 14–17) in 2 IDP camps, northern Uganda (n = 304)								Significant decline in depression from baseline to follow-up in IPT intervention (42.9 →  24.9, p=0.002) v. control (44.2 → 36.1) but not in creative play Greater reduction in depression among girls than boys
(Catani et al., 2009)**	RCT of KIDNET v. MED-RELAX delivered to war-affected children (girls and boys, aged 8-14) in post-Tsunami IDP camps, Manadkadu, Sri Lanka (n = 31)								Significant reduction in PTSD diagnosis at 6 months follow-up (p<0.001): 81% of KIDNET group and 71% of MED-RELAX group did not reach threshold for PTSD diagnosis. No significant difference between groups
(Dybdahl, 2001)	RCT of semi-structured group therapeutic discussion delivered to mothers (aged 20-44) living in refugee settlements and private accommodation for IDPs in Tulza, Bosnia (n = 42)								Significant improvement in well-being (+1.93, p<0.05), sense of social support (+1.71, p<0.05), reduction in arousal (−2.00, p<0.05) in intervention v. controls
(Freij, 2018)	Qualitative evaluation (interviews and FGDs) of livelihood programme delivered to IDPs (males and females, aged 18–35) in Dohuk Governorate, KRI (n = 72)								42% of those surveyed stated that the intervention helped to improve their psychological well-being 98% said their relationships with families, friends and neighbours had improved
(Kaya and Luchtenberg, 2018)	Qualitative evaluation (interviews and FGDs) of livelihood programme delivered to IDPs (males and females, aged ≥18) in camps and settlements across KRI (n = 129)								Participants stated positive feelings of empowerment, independence and well-being through enrolment in the programme
(Lancaster and Gaede, 2020)	Pre and post-test experimental study of a resiliency programme delivered to IDPs (males and females, aged 12–98) in Khanke, Essien, Kabarto and Soran camps, KRI (n = 766)								Significant improvement in PTSD symptoms pre and post-intervention (29.41 → 13.32) and follow-up (14.42), p<0.001 Greater decline in female participants (35.81 → 12.85) than males (25.74 → 13.63)
(Nakimuli-Mpungu et al., 2013)	Quasi-experimental study of group therapy intervention delivered to war-affected IDPs (males and females, aged ≥18) in four trauma clinics, northern Uganda (n = 613)								Faster reduction in depression symptom scores in intervention v. control group at 6 months follow-up (−3.38 → −0.30), p=0.019] Faster reduction in PTSD scores in intervention group v. control group at 3 months (−4.21 → −0.10), p=0.042] 3-months follow-up: participants who attended ⩾2 sessions had faster increases in functioning scores than those who attended one session
(O'Callaghan et al., 2013)	RCT of TF-CBT delivered to war-affected girls (aged 12–17) rescued from brothels in Beni, DRC (n = 52)								TF-CBT group experienced reductions in PTSD from pre-post intervention (40.88 → 18.38, p<0.001) v. control group (40.29 → 42.93), and significant improvements in symptoms of depression/ anxiety (37.96 → 13.96, p<0.001) v. control (39.18 → 40.04)
(Schaal et al., 2009)	RCT of NET v. IPT delivered to youths (males and females, aged 14–28) living in child-headed households and orphanages in Kigali, Rwanda (n = 26)								6-month follow-up: 25% of NET and 71% of IPT participants fulfilled PTSD criteria Mean depression scores significantly decreased in both intervention types (IPT = 6.57 → 4.79, p=0.05; NET = 6.00 → 5.00, p=0.05)
(Schneider et al., 2018)	Case-control study of NET delivered to IDPs (males and females, aged 18-80) in former IDP camps (Anaka, Pabbo, Koch Goma) and villages (Gulu and Nwoya district), Uganda (n = 1131)								Reduction in prevalence of PTSD diagnosis following NET intervention for group with perceived stigmatisation at 4 months follow-up (166 →  60, p=0.015) and 10 months follow-up (166 → 15, p=0.004)
(Seidi et al., 2020)	Case series study of CBT v. thought field therapy (TFT) delivered to IDPs (males and females, aged 18-43) receiving treatment at two centres in Kalar City, KRI (n = 31)								Of 13 participants who received CBT, only one experienced improved PTSD and anxiety symptoms 11 participants who received TFT showed improvement in symptoms of PTSD and/or anxiety 7 participants who received CBT and showed no improvement then showed improvement when subsequently enrolled in TFT
(Sonderegger et al., 2011)	Case-control study of CBT delivered to IDPs (males and females, aged 15-56) living in Pabbo and Ajulu IDP camps, Uganda (n = 202)								Significant reduction in three depressive scales at post-assessment (p<0.001) and at 3-months follow-up (p<0.001) for participants in intervention group Significantly lower anxiety scores for intervention v control group (p<0.001), maintained at 3-months follow-up (p<0.001)
(The Lotus Flower, 2017)	Annual report assessment of art therapy delivered to IDPs (females, aged ≥18) in Rwanga camp, Dohuk governorate, KRI (n = 85)								Interviews with participants indicated improved well-being 85 women graduated from the intervention 35 earned an income through local contracts
(Womersley and Arikut-Treece, 2019)	RCT of psychotherapy, EMDR, art therapy, delivered to Free Yezidi Foundation Women's Centre members (females, aged ≥18) in Khanke IDP camp, Dohuk governorate, KRI (n = 200)								74% increase in self-reported WHO-5 well-being scale among service users PTSD decreased significantly upon completion of programme (81.25% → 45%)
(Yeomans et al., 2010)	RCT of 3-day trauma workshop with and without psychoeducation delivered to participants (males and females, mean age 38.6 years, SD =12.8) in two IDP camps in rural Burundi (n = 113)								Participants in workshop without psychoeducation had greatest reduction in PTSD (2.25 →  1.89) v. control (2.04 →  2.11), p<0.01 and v. those in workshop with psychoeducation (2.14 → 1.97), p<0.05
TOTAL		10	16	7	9	8	9	12

Footnote: *Acaturk et al., 2016. Record was included despite intervention delivery to Syrian refugees as camp was located on the Syrian border. **Catani et al., 2009. Record was included due to exposure to war experiences, but note additional exposure to Tsunami.