Table 1. Outline of study characteristics in Zambia and Lesotho.

Characteristics	Zambia	Lesotho
Study site	Ngungu-Bwacha, Kabwe town in Central Province	23 Villages in the district of Butha-Buthe, Lesotho
Study population	Peri-urban community (high HIV and TB)	Semi-urban to rural community (high HIV and TB)
Outreach strategy	Walk-in individuals at community hubs *Door-to-door was added in the last two weeks of study	Active recruitment of individuals by community health workers (CHW) in the villages
Inclusion criteria	• ≥15 years • currently residing in the community • able to give informed consent	• ≥18 years • currently residing in the community • showing COVID-19 symptoms and/or COVID-19 contact • no signs of severe symptoms • able to give informed consent
Study period	3 months February-April 2022	11 months August 2021-June 2022
Ag-RDT used	SD Biosensor STANDARD Q COVID-19 Ag Test (SD Biosensor; Republic of Korea)	SD Biosensor STANDARD Q COVID-19 Ag Test (SD Biosensor; Republic of Korea)
Swab used for self-testing and for testing by CHW	Nasal	Nasal
Professional user	Trained community health workers	Trained community residents that work together with the ministry of health and provide basic preventive primary health care services.
Study procedures	Cognitive interviews (did not change IFU) Self–testing following manufacturer’s IFU No assistance from study staff CHW blinded to self-testing result Observation of self-testing Ease of use questionnaire	Cognitive interviews (IFU was adapted according to results) Self-testing following adapted IFU With assistance from study staff CHW not blinded to self-testing result