Table 4.

Summary of articles discussing working in low-literate settings, and with indigenous or less commonly spoken languages

Reference (year)	Study description	Study location	Major findings
Mboizi et al 22 (2017)	Mixed methods research—Recall and decay of consent information among parents using an audiovisual tool	The Gambia	Recall of trial procedures and consent process was evaluated using questionnaires at two points in time. Results show overall good recall of consent when using the Speaking Book audiovisual tool. No differences were found between age, occupation, years of education, religion and family type.
Kalabuanga et al 18 (2016)	Case study—Description of the consent process during a malaria clinical trial	Democratic Republic of Congo	Authors identified misunderstanding of the informed consent process among parents. They also identified cases where culturally accepted guardians might not have legal authority to consent for research. They discuss how the use of a witness can impair parents’ autonomy by exerting social pressure. In the context of limited access to care, the ancillary benefits of participating in research may be a strong incentive to participate.
Martellet et al 17 (2015)	Case study—Informed consent for a vaccine trial	The Gambia, Mali, India, Senegal, Ghana	Informed consent for a vaccine trial was sought from parents/legal guardians of children aged 1–17 years. Written assent was taken from children aged 12–17. They used literate witnesses when participants/parents were illiterate and translated consent forms to local languages. In some areas, consent was done verbally. Written consent forms were always provided. Some study sites used tools to assess understanding of the research project prior to consent.
Tindana et al 52 (2012)	Qualitative—Interviews with research staff and mothers of study participants about the informed consent process for a malaria genetics study	Ghana	The consent process was adapted to include community leaders and groups of women. For individual consent, written forms were used but information was adapted to be more relevant to parents. The timing of consent for inpatient cases was modified to obtain it after children had been stabilised. The provision of medical care and direct benefits to children was identified as a motivation for participating.