James 2020.

Study characteristics
Methods	Study design: RCT Study grouping: parallel group Study duration: 12 weeks
Participants	Inclusion criteria: interviewers approached every 5th dwelling in the order encountered when walking through the community, starting from the side of the community most affected by flooding in past seasons. At each household, researchers used a recruitment script to assess interest and eligibility (aged 18–65 years; household decision‐maker; availability to attend 3‐day intervention training). There were no specific screen out or in criteria, assuming the community member was able to give consent. Exclusion criteria: not reported Age range: 18–65 years Gender: 239/480 (49.8%) women, 241/480 (50.2%) men Intervention sample: 240 Control sample: 240 Main type of traumatic event: compounded stressors Phase of humanitarian crisis: during the acute crisis (mortality was still higher than it was before the crisis). Study conducted between July 2014 and April 2015. Type of humanitarian crisis: natural disaster
Interventions	Intervention name: Mental Health Integrated Disaster Preparedness Intervention Delivered by: para‐professionals: 2 trained Haitian lay mental health workers Format of therapy: face to face Number of sessions (total): 3 Type of control: waiting list Type of intervention context: community setting Type of promotion intervention: group level Description of the intervention: the Mental Health Integrated Disaster Preparedness Intervention utilises an experiential approach, including facilitated discussion, space for sharing personal experiences and exchange of peer‐support, establishing safety and practicing coping skills targeting disaster‐related distress, and hands‐on training in disaster preparedness and response techniques for use by participants in their own lives and to support other community members.
Outcomes	Acceptability (dropout from trial) Outcome type: dichotomous outcome Reporting: fully reported Data value: endpoint
Notes	Sponsorship source: Research for Health in Humanitarian Crises (R2HC) Country: Haiti Setting: rural communities in Port‐au‐Prince Author's name: Leah Emily James Institution: University of Colorado Email: leah.james@colorado.edu Address: Institute of Behavioral Science, Natural Hazards Center, University of Colorado‐Boulder, 483 UCB, Boulder, Colorado 80309‐0483, USA
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Randomization occurred using a random number generator applied to participant lists." No further information reported on the method of random sequence generation, but the balance of participant‐level characteristics suggests that the randomisation procedures were successful.
Allocation concealment (selection bias)	Unclear risk	Allocation concealment procedures were not reported.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Blinding procedures were not reported; however, it is likely that participants were aware of their treatment allocation because the trial was open label.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Quote: "Due to staffing constraints, interviewers were not blind to condition, as team members served as both interviewers and intervention facilitators (though participants were not typically interviewed by the same staff person who facilitated their group's intervention)."
Incomplete outcome data (attrition bias) All outcomes	High risk	High attrition rates: 78/240 (32.5%) dropouts in the intervention group and 94/240 (39%) dropouts in the wait‐list group.
Selective reporting (reporting bias)	Low risk	All measures described in the methods section of the article were also reported in the results. No trial protocol available but trial registered at Clinical Trials Registry‐India (CTRI/2018/02/012002).
Therapist qualification	Unclear risk	No information provided on therapist qualifications and background.
Therapist/investigator allegiance	Unclear risk	No information provided.
Intervention fidelity	Unclear risk	No information on how fidelity to intervention was recorded/checked.
Other bias	Low risk	No other sources of bias detected.