Trial participants' understanding of randomization, double-blinding, and placebo use in low literacy populations: findings from a study conducted within a microbicide trial in Malawi.

ABSTRACT

Concerns have been raised about the limits of understanding of consent by clinical trial participants in developing countries. Consequently, this empirical study was conducted in Malawi to assess microbicide trial participants' understanding of randomization, double-blinding, and placebo use. The study used a combination of quantitative and qualitative methods, including structured questionnaire interviews with a random sample of 203 individual participants, four in-depth interviews with research nurses, and two focus group discussions with 18 study participants. Most respondents earned high scores on questions related to randomization (85%) and placebo use (72%), while a greater proportion of the same respondents obtained low scores on questions related to double-blinding (68%) and personal implications of the study procedures (63%). Overall, most respondents (61%; n = 124) obtained low scores on combined understanding of all the three concepts under study.