Informed Consent Documents: Too Long?

October 31, 2011

Kass, N., et al., “Length and Complexity of U.S. and International HIV Consent Forms from Federal HIV Network Trials,” 26 (11) J. Gen. Int. Med. 1324-8 (August 2011), argue that shorter, more easily understandable clinical trial consent forms are needed so that trial subjects can better understand research projects. The authors reviewed 124 informed consent forms from NIH-sponsored multinational HIV/AIDS trials conducted in 2006. They determined that the median form was 22 pages long with a median readability at the 9.2 grade level. Confidentiality sections were written at the 12.35 median grade level. In contrast, the authors claim, almost half of Americans read at or below the eighth-grade level. In some foreign countries, where research is increasingly carried out, a majority of the population is illiterate. For example, the literacy rate in India is 63 percent, in Bangladesh 55 percent and in Senegal 42 percent. The authors assert that for those with low literacy, less information actually correlates with improved understanding.

The authors also criticize the consent documents studied for failing to provide more complete explanations of research concepts such as randomization and placebos. The comparatively cursory treatment of these subjects contrasted with two-page-long confidentiality sections. The authors did observe that federally required topics such as purpose, procedures and risks were typically discussed in detail in domestic consent forms.

The authors purported to compare the consent documentation in U.S. trials versus that in foreign trials. They found international forms to be easier to read than the American ones. Perhaps not surprisingly, the adult forms were less complicated than the pediatric (parent) ones.


Informed consent to clinical trials is governed mainly by 21 CFR Parts 50 and 56, particularly 21 CFR 50.25(c). FDA does not provide a template, nor does it impose any specific length requirement. Kass, et al., complain about the length and complexity of the documents they analyzed. Although improved understanding is desirable, explaining concepts such as randomization and placebos, even with aggressively economical use of language, will likely lengthen, not shorten, consent forms.

The Kass study considers consent documentation solely from the viewpoint of enhancing subject understanding. Although such a goal is desirable, it is not the sole function served by a consent form, particularly here in the United States. See, e.g., Mello, M.M., et al., “The Rise of Litigation in Human Subjects Research,” 139 Ann. Int. Med. 40-45 (2003). Consent forms are long and involved because trial sponsors and investigators are trying to comply with the requirements of the law and to avoid accusations of failing to do so. If criticism is called for, its target should not be PIs, IRBs or trial sponsors. Its target should be the tort system and the plaintiffs’ bar. Before trial sponsors, PIs, IRBs and other interested persons consider modifying consent forms, they should seek better liability protection via tort reform, lest changes intended to improve the informing function of these documents increase liability exposure. They should also seek advice of counsel. Kass, et al., may believe that, with respect to information, less is more. Plaintiffs’ counsel are highly unlikely to share that view.