Short and sweet? Do study participants prefer shorter or longer consent forms? Do they understand the contents?

Editor’s notes: As described above in the HOLA en Grupos study, engagement and partnership is vital if HIV research is to produce useful and relevant results.  The ethics of research involving human subjects continues to evolve but the key principles laid out by Beauchamp and Childress in 1989 [1] remain central.  The principles of autonomy, non-maleficence, beneficence, and justice, have been extremely influential in the field of medical ethics, and are fundamental for understanding the current approach to ethical assessment in health care.

Autonomy implies that research participants should be able to consent willingly to join a research study and a key part of that informed consent process is usually a written “consent form” that is signed by the participant.  However, a major challenge is often to ensure that on the one hand all relevant information about possible benefits and harms is included in the information and on the other hand that the consent process is manageable and appropriate for the participant.

In the largest study of its kind to date, Grady and colleagues embedded a randomized trial within the larger randomized START trial (comparing immediate with deferred start of antiretroviral medicines in people with early HIV infection).  Around 4000 participants in START were allocated according to their 154 research sites, which were randomly assigned to the original, lengthy and somewhat complicated consent form, or to a simplified, shorter consent form with much more attention paid to ease of comprehension and readability.  The shorter form was still around 1800 words long (compared to the almost 6000 of the original) and was only a little easier to read, because the sponsors of the study needed to be certain that all the information demanded by current guidelines was included.

Surprisingly, there was no overall difference in either the primary outcome (an understanding that participants’ treatment would be randomly allocated) or in overall comprehension of aspects of the study.  In other words, the authors did NOT find the advantages that they were expecting from the modified consent form.

However, various clear trends emerge from the data that are relevant to future research too.  Those with less education were clearly less able to understand the randomization approach.  73% of the 1240 participants who had not attended high school compared to more than 90% of the 935 who had completed a university degree or postgraduate education answered the primary question on randomization correctly. The START study team were diligent in explaining the study to potential participants before presenting the informed consent form, with around a half of participants reporting more than an hour of explanation prior to being asked for consent, and more than 80% of sites reporting that participants understood the study “very well” prior to the consent process.  There was also a clear trend for participants from sites that had been involved in previous HIV research to understand the process better (rising from 69% in those with no previous HIV studies to 85% in those with more than 10).

Increasingly HIV prevention researchers are aiming to work with populations that have high ongoing incidence of HIV.  In a world where treatment is increasingly widespread and overall numbers of infections have fallen somewhat, this means that researchers will tend to be working with more and more disadvantaged populations where many participants may be less well educated and less familiar with research.  This important study makes it clear that the ethical principle of autonomy requires an ongoing process that goes far beyond the choice of words in a consent form.  Research must build trust between researchers and participants.  The research team should explain carefully and in appropriate ways what is involved in the study and what options participants have. Study teams should build a governance process into the research so that participants can have confidence that any risks of the research, both for them as individuals, but also often for the community or group to which they belong, are monitored and mitigated.  In this way potentially vulnerable individuals may still be recruited into important research projects and contribute to the ways in which science can end the epidemic.

A randomized trial comparing concise and standard consent forms in the START trial.

Grady C, Touloumi G, Walker AS, Smolskis M, Sharma S, Babiker AG, Pantazis N, Tavel J, Florence E, Sanchez A, Hudson F, Papadopoulos A, Emanuel E, Clewett M, Munroe D, Denning E; INSIGHT START Informed Consent substudy Group PLoS One. 2017 Apr 26;12(4):e0172607. doi: 10.1371/journal.pone.0172607. eCollection 2017.

Background: Improving the effectiveness and efficiency of research informed consent is a high priority. Some express concern about longer, more complex, written consent forms creating barriers to participant understanding. A recent meta-analysis concluded that randomized comparisons were needed.

Methods: We conducted a cluster-randomized non-inferiority comparison of a standard versus concise consent form within a multinational trial studying the timing of starting antiretroviral therapy in HIV+ adults (START). Interested sites were randomized to standard or concise consent forms for all individuals signing START consent. Participants completed a survey measuring comprehension of study information and satisfaction with the consent process. Site personnel reported usual site consent practices. The primary outcome was comprehension of the purpose of randomization (pre-specified 7.5% non-inferiority margin).

Results: 77 sites (2429 participants) were randomly allocated to use standard consent and 77 sites (2000 participants) concise consent, for an evaluable cohort of 4229. Site and participant characteristics were similar for the two groups. The concise consent was non-inferior to the standard consent on comprehension of randomization (80.2% versus 82%, site adjusted difference: 0.75% (95% CI -3.8%, +5.2%)); and the two groups did not differ significantly on total comprehension score, satisfaction, or voluntariness (p>0.1). Certain independent factors, such as education, influenced comprehension and satisfaction but not differences between consent groups.

Conclusions: An easier to read, more concise consent form neither hindered nor improved comprehension of study information nor satisfaction with the consent process among a large number of participants. This supports continued efforts to make consent forms more efficient.

Trial registration: Informed consent substudy was registered as part of START study in clinicaltrials.gov #NCT00867048, and EudraCT # 2008-006439-12.

Abstract [2] Full-text [free] access  [3]

Africa [5], Asia [6], Europe [7], Latin America [8], Northern America [9], Oceania [10]
Argentina [11], Australia [12], Brazil [13], India [14], Israel [15], Malaysia [16], Mali [17], Mexico [18], Nigeria [19], South Africa [20], Thailand [21], Uganda [22], United States of America [23]
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