BackgroundThe informed-consent process should be one of meaningful information exchange between researchers and study participants. One of the responsibilities of research ethics committees is to oversee appropriate informed consent. The committee must consider various matters before deciding whether the process is appropriate, including the adequacy and completeness of the written information provided to study participants, and the process of obtaining informed consent.This study aimed to identify, quantitatively and qualitatively, consent-related issues in different types of malaria proposals submitted to the Faculty of Tropical Medicine, Ethics Committee.MethodsThis study reviewed proposal documentation submitted to two panels of the Ethics Committee of the Faculty of Tropical Medicine, Mahidol University, from 2011 to 2015. The documentation included proposals, notifications to researchers of review outcomes and ethical issues of concern to committee members. Each element of the informed-consent process was identified and analyzed by study classification, design, and specimen use, including whether the study involved a vulnerable population. Summative content analysis was used to analyze patterns of common issues raised in reviews.ResultsOf the 112 proposals reviewed, 63 required an informed consent process. All researchers proposed communicating with their study participants; however, about two-thirds needed to improve their explanations of study procedures (study activities and specimen/data-collection process) to participants. About 40% of the proposals attracted comments on informed-consent process elements--risk and discomfort, vulnerable status, and compensation. Studies that planned to collect or use new/linked specimens raised more issues around informed consent than studies using linked data/records. Studies that involved vulnerable populations raised more issues than those that did not. The committee usually asked researchers to clarify, elaborate, revise, or paraphrase the consent process elements that were considered to involve inadequate information exchange between researcher and study participant.ConclusionsThis study aimed to describe lessons for malaria researchers about common informed-consent process issues in different types of malaria proposals. The information and analysis of informed-consent elements should assist the preparation of malaria-research proposals.