In this study, we compared patients’ comprehension and satisfaction of current informed consent procedures in routine clinical care with the level of comprehension and satisfaction of patients treated within clinical trials at the same comprehensive cancer center in a real-world scenario.
To evaluate the effectiveness of an informed consent process, individual comprehension must be divided into subjective and objective, testable comprehension . Most patients in both surveys indicated a high level of comprehension, which, considered from an objective point of view, was not always accurate. For example, 20% of the patients in both cohorts were not able to name their cancer diagnosis correctly. Additionally, uncertainty about the proposed treatment was present in both cohorts. About 11% of the patients treated within a clinical trial knew the purpose of the trial only partially or not at all, indicating a lack of comprehension. However, it must be pointed out that during the interview patients could rate the information given (too much, just right, too little) and on average, all participants rated the information given as “just right”. Patients only rated the topic “contraception” as too extensive, which might be an irrelevant issue for many patients since the median age at study inclusion was 58 years. Overall, results might be too positive here due to an interviewer bias. The partial uncertainty could also be linked to the fact that most patients in survey 1 took very little time reading the informed consent form: More than 70% of the patients reported they read it completely. 40% indicated they read it in less than 15 minutes, yet the material contained up to 40 pages. Objectively, patients must have rather quickly skimmed the material than really reading it carefully in that short amount of time. In contrast to this, the level of uncertainty was higher in patients from cohort 2: for 18% of the patients the treatment goal remained partially unclear and 7% of the patients did not know the treatment goal at all. Subgroup analysis showed that these patients received palliative treatment, which implies communication weaknesses between the treating oncologists and the patients, since full disclosure of a life-threatening diagnosis can be challenging and misconception in cancer communication is a common problem . Retrospectively, 40% of the patients missed information about alternative therapies. About 20% of the patients from both surveys had troubles understanding the consent form in some parts. However, the statement “I had to ask a lot of questions to understand the informed consent form” was affirmed by only 10% in each cohort, indicating a potential disinterest to understand each detail. This might hold true especially for patients in survey 2, since almost three times as many patients receiving standard cancer therapy affirmed the statement “I just wanted to sign the informed consent form” (29% in survey 2 versus 11% in survey 1), indicating that participants in clinical trials prefer to know more details than patients receiving standard care. However, each 10% of the patients in both cohorts did not read the information material at all. Noticeably, patients’ perception of the informed consent talk differed quite much: in both cohorts, patients were asked whether they felt reassured after their informed consent talk. Whereas 48.5% of the patients from survey 2 fully agreed here, only 12% of the patients from survey 1 agreed. This might be additional evidence for uncertainty or comprehension troubles.
Jefford et al. performed a similar study to examine knowledge and satisfaction regarding the informed consent process concerning cancer clinical trials with 102 patients being treated in 27 different therapeutic trials . In line with our findings, the authors stated that knowledge regarding cancer clinical trials was generally good, but significant information was frequently missing, e.g. each 12% of the trial participants missed information on the specific cancer being studied, the reason for research, or other treatment options available . Importantly, satisfaction correlated with perceived but not objective understanding , what we could also demonstrate in our surveys.
Various attempts to overcome comprehension limitations have already been discussed. A larger font size and stronger contrasts as well as a concise and simpler language may help to improve the readability. [20, 21] Multimodal approaches to optimize the quality of the informed consent process - not only in the setting of cancer therapy - have shown promising results, e.g., the use of touch-screen tablets, animated videos, slideshows with voice-over or comics [22, 23] or feedback interventions . However, none of these attempts have yet been implemented into the real-world scenario of patient education, even though we have been aware of these shortcomings for years.