Table A1.

Shows the steps and criteria for participant selection for the cognitive interviewing.

Recruitment of participants	Centres were selected based on the availability of mental health services, on their participation in the National Mental Health Programme activities, and on typical patients’ demographics (Lebanese, or Syrian or Palestinian nationalities)
	In total, three mental health professionals and 13 PHCC front-line workers were interviewed, 64 community members including Lebanese, Syrian and Palestinian nationalities participated in FGDs, and two community members were interviewed individually for more in-depth information
	PHCCS helped recruit participants from among their beneficiaries for the FGDs by approaching them while in the waiting room. Two front-line workers were interviewed from each centre and one or two FGDs took place in each centre for women (n  =  38) and men separately (n  =  26)
	People of these three nationalities, above 18 years of age, and with primary school level literacy (in order to be able to engage with the Step-by-Step materials) were included in the study
	The focus group participants were not screened for depression. Participants completed a written consent form with the assistance of the data collector where necessary and were remunerated US$15 for their time