Observed Behaviors of Subjects During Informed Consent for an Emergency Department Study

Article Outline

• Abstract
• Introduction
  • Background
  • Importance
  • Goals of This Investigation
• Materials and Methods
  • Study Design
  • Setting and Selection of Participants
  • Methods of Measurement
  • Primary Data Analysis
• Results
• Limitations
• Discussion
• References
• Copyright

Study objective

To determine emergency department patients' behaviors during informed consent for an intimate partner violence survey.

Methods

We conducted a cross-sectional study during administration of informed consent. Research assistants recorded whether informed consent was read, time spent reading it, whether questions were asked, and whether the patients took a copy of the form that was handed to them. Results are reported as percentage of frequency of occurrence.

Results

Of 1,609 patients approached for the intimate partner violence study, 1,312 (82%) patients participated. After verbal description of the study, 53% of patients read the informed consent but only 13% spent more than 2 minutes doing so. Only 20% of patients asked questions and less than half (49%) accepted a copy of the form when it was handed to them.

Conclusion

Patients who participated in an intimate partner violence study did not spend a lot of time reading the consent document, asked few questions, and did not take the copy of the consent form with them. Future studies of the current consent process should determine whether it provides adequate human subjects protections in a manner desired by the patient.

SEE EDITORIAL, P. 15.

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Introduction 

Background 

Protection of human subjects participating in research involves informed consent on the part of the participants, as well as oversight by local institutions where the intended research is to be performed.¹ Informed consent and institutional oversight are regulatory policies stipulated by the federal government for all federally funded research.² All other research largely follows these rules because protection of human subjects is vitally important. The rapid changes in clinical medicine, funding sources for research, and the organization of health care systems has led many to question the adequacy of protective measures for human subjects.³, ⁴, ⁵ Reorganization at the federal level, with the creation of the Office of Human Research Protection, suggests that there is much work to be done to address these issues.⁶

The goal of the informed consent process for research is a clear understanding on the part of the potential subject of what is being proposed so the potential subject can make an autonomous decision about participation. During the informed consent dialogue, essential elements must be transmitted from investigator to participant. These include but are not limited to the purpose of the research, risks, benefits, and alternatives to participation. The signed written informed consent form helps document this dialogue.⁶

Importance 

The informed consent process for research in emergency medicine has not been extensively studied, and in an extensive literature search, no studies could be found that focused specifically on emergency department (ED) patient behaviors during the informed consent process. Most investigations have focused on the issues of readability and literacy of consent forms. Although emergency medicine researchers are subject to the same regulatory process for research as their counterparts in other specialties, research in the ED setting is uniquely characterized by several issues. Emergency patients often lack familiarity with the clinical environment, rarely have previous relationships with emergency providers, and may be too acutely ill, too debilitated, or in too much pain to provide optimal or even valid informed consent.

Goals of This Investigation 

To gain more information about the informed consent process in the ED setting, we designed the following as a prespecified secondary study of a larger study evaluating the effects of written informed consent on the detection of intimate partner violence during ED screening.⁷ Our primary objective was to determine whether ED patients participating in a survey study on intimate partner violence read the written informed consent document. Secondary objectives were to ascertain the time spent reading the document, whether the patient asked questions about the study, and whether patients accepted a copy of the informed consent document when it was offered to them.

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Materials and Methods 

Study Design 

This cross-sectional survey was part of a larger study examining the effect of informed consent on intimate partner violence screening.⁷ The study was conducted in an adult, urban, academic ED with an annual census of approximately 51,000 patients.

Setting and Selection of Participants 

The study population consisted of consecutive patients aged 18 to 65 years who presented to the ED 16 hours a day, from 8 am until midnight on even calendar days during a 10-week period in 1999. This study was approved by the Institutional Review Board of the University of Pennsylvania. We excluded patients who were non-English speaking, were judged to be too ill or injured to approach for informed consent, or had altered mental status as a chief complaint. Ninety-five percent of the patients presenting to the ED of the Hospital of the University of Pennsylvania are English speaking. Patients were also excluded if they identified themselves as University of Pennsylvania or Hospital of the University of Pennsylvania students or employees. This was done to prevent any conflicts or breaches of confidentiality that could occur because many of the research assistants were students at the same university.

Informed consent was obtained by trained research assistants. Their training included a 3-hour role-playing session that focused on how to approach patients, with the use of a script to obtain informed consent, followed by two 6-hour one-on-one sessions with a more experienced research assistant in the ED. During the one-on-one training, the research assistants first observed the experienced researcher obtaining informed consent from an ED patient and later were observed and critiqued on their attempts to obtain informed consent.

After reading a scripted introduction and describing the study, research assistants handed the patients the written informed consent document to read. Patients were given the opportunity to read the document and to ask questions. Subsequently, they were asked for their signature if they indicated willingness to participate. Finally, patients were provided with a copy of the informed consent form if they agreed to participate in the study.

The written informed consent document was brief (2 pages, 11 paragraphs) and contained standard institutional review board injury, compensation, confidentiality, and subjects' rights statements. The study objective paragraph for the main study stated, “To determine the results of a screening process for domestic violence with a verbal versus a written informed consent.” The study procedure was described in one sentence indicating the patient would be asked a few questions pertaining to violence in the home. The risks noted to the patient were “embarrassment or retaliation should a potential assailant learn of your answers.” There were no direct benefits stated, but the patients were told they would receive a referral sheet of support groups in the area for outpatient counseling and legal advice if warranted or desired. This referral sheet was also made available to those patients who chose not to participate.

Methods of Measurement 

The trained research assistants observed and recorded the following patient behaviors: whether or not the patients read the informed consent form, time spent reading the form, whether the patients asked questions, and whether they accepted a copy of the form when it was handed to them. Research assistants were not given any specific instructions on how to observe patients as long as they recorded the variables of interest. In some cases, research assistants remained at the bedside and in other cases they returned after observing patients from a distance. In addition, demographics and health characteristics of the study population were recorded as part of the larger study.⁷

Primary Data Analysis 

Data were analyzed with the χ² or Fisher's exact test for categorical data and Student's t test for continuous data, with regard to patient characteristics. Main outcome variables are expressed as frequencies and percentages, with 95% confidence intervals (CIs). All data were analyzed with SAS statistical software (version 8.0; SAS Institute, Inc., Cary, NC).

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Results 

Eighty-two percent (1,312/1,609) of eligible patients agreed to participate in the intimate partner violence informed consent study and were thus eligible to have their behaviors observed. The participants were predominantly young, women, black, and not married (Table). Patients who did and did not consent to participate in the main study were similar with respect to age, sex, race, and chief complaint classification.

Table. Characteristics of the study population.

Characteristic	No. (n=1,312)	Percentage
Age, y, mean (SD)	36.8(12.3)
Female sex	772	59
Black	842	64
Unmarried	872	66
Education for <12 y	243	19
Self-reported health status
Generally healthy	226	17
Average health	309	24
Below average health (sickly)	711	54

Eighty-one percent (1,062) of the study population had some form of health insurance and 13% (174) were characterized as self-paying. Seventy-one percent (936) reported having a primary care provider. Most patients described their health as average or below average (Table). Fifty-four percent (703) of participants had been previously admitted to a hospital at some point in their life. A majority, 69% (903), of the study population had previously been to an ED.

The results of the observed patient behaviors showed that only 53% (689) (95% CI 49% to 55%) read the informed consent form at all (Figure). Of those who did read it, 20% (136) spent less than 10 seconds, 38% (259) spent less than 1 minute, 30% (208) spent between 1 and 2 minutes, and 13% (92) spent more than 2 minutes doing so. Only 20% (264) (95% CI 18% to 22%) of patients asked questions about the study and 49% (644) (95% CI 46% to 52%) took a copy of the form when it was handed to them.

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• Figure. 

  Amount of time that patients spent reading the consent form.

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Limitations 

Although our research assistants did receive formalized training on the importance and mechanics of informed consent procedures, their relative inexperience might have contributed to patients not being more invested in the informed consent process. We did not attempt to standardize the way that research assistants observed patients, and their own choice of behaviors may have influenced the way the patient reacted and behaved during the process. We also did not have an additional observer watch the consent process. Patients who were “too ill or injured” were subjectively excluded from the study. It is not known whether a sicker group of patients would have demonstrated behaviors that were more or less optimal during the informed consent process. We did not attempt to assess literacy in our study population, so we cannot be sure whether some patients were unable to read the consent document. We also did not capture behaviors of the patients who declined participation in the larger study. Whether they may have spent more or less time reviewing the consent is unknown.

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Discussion 

Our study showed that a minority of patients fully read, questioned, or actively accepted a copy of a written informed consent document associated with a cross-sectional ED survey study on the subject of intimate partner violence.⁷ To our knowledge, previous studies have not focused on the informed consent process for research in emergency medicine, and in an extensive literature search no studies could be found that focused specifically on patient behaviors associated with this process.

Existing literature on this topic has instead focused on improving patients' understanding of the informed consent document and process through a variety of methods, including but not limited to modifying the consent form, engaging in an extended discussion with the patient, or using multimedia approaches.⁸ A recent systematic review examined the effect of various interventions on the improvement of research participants' understanding of information in the informed consent document. All of the studies in this review compared understanding in a control group exposed to a standard informed consent process with understanding in an intervention group exposed to multimedia, enhanced consent forms, extended discussions, and testing or feedback designed to improve understanding.⁸

On careful examination of the systematic review, the multimedia interventions failed to improve research participants' understanding; only 2 studies showed improved retention of information weeks later.⁹, ¹⁰, ¹¹, ¹², ¹³, ¹⁴, ¹⁵ Fifteen studies using enhanced consent forms evaluated the effects of one or more of the following strategies to modify the consent form: condensing the length, revising the content to make it more comprehensible and readable, improving formatting through the use of techniques such as larger font size and italics, and adding graphics. None of these approaches proved more successful than others. Six of the studies showed significant gains in understanding, but 5 of these were simulated consent scenarios in which the control group read the original informed consent form, the experimental group read the modified informed consent form, and the control and experimental groups' understanding was assessed. The improvements in understanding because of enhanced consent forms may be unrealistic in real research context in which some information is obtained through discussion.⁹, ¹⁰, ¹⁶, ¹⁷, ¹⁸, ¹⁹, ²⁰, ²¹, ²², ²³, ²⁴, ²⁵, ²⁶, ²⁷

The 5 extended discussion studies included interventions ranging from 30-minute telephone conversations with a nurse to multiple counseling sessions lasting up to 2 hours. The extended discussion interventions resulted in statistically significant increases in understanding in 3 of the 5 studies, and the remaining 2 showed trends toward improvement in understanding.¹¹, ²⁸, ²⁹, ³⁰, ³¹ For the 5 test/feedback interventions examined, researchers quizzed patients about the information disclosed to them and were given a review of questions they answered incorrectly. All 5 test/feedback studies showed a significant influence on understanding (all P<.05).²³, ³², ³³, ³⁴, ³⁵ Overall, one can conclude that focusing on the dialogue between patient and researcher and using test/feedback mechanisms are the greatest means of improving patient understanding, whereas modifying consent forms (in length and reading level) and multimedia approaches have proven far less effective.

The systematic review included only one study performed in an ED setting, which examined modified, shortened consent forms and patients' ability to retain information.¹⁹ This study found modified consent forms to be more effective. The group of enhanced consent form studies also included vulnerable patient populations (the elderly and the mentally ill), providing some insight into the unique vulnerabilities of ED patients.³⁶ An additional consideration for the use of an enhanced consent form in the ED is that the heavy dependence on the form to convey essential information can prove problematic with severely injured, disoriented, or emotionally distraught patients.

An extended informed consent discussion would be applicable to an ED setting on a case-by-case basis. Extended discussion requires between 30 minutes and 2 hours for both the patient and the researcher. These discussions may be desired by patients in more complex studies. Patients may not have believed that such a lengthy review process was necessary for the relatively brief survey we were assessing. In more complex or higher-risk studies, patients may prefer more lengthy discussions. Patients remain in the ED for various amounts of time, and such lengthy discussions require that special consideration be taken to avoid interfering with patient care. In addition, the extended discussion requires a greater time commitment from personnel and may prove costly when those administering the informed consent are paid for their time. Well-trained volunteers would increase the feasibility of the extended informed consent discussion in the ED.

Finally, the majority of the test/feedback interventions could be easily translated to the ED setting. Test/feedback interventions have been conducted with vulnerable populations and are often brief (one was 15 minutes or less). The process could be modified with in-person follow-up testing for those patients admitted to the hospital hours or even days after informed consent, and for patients discharged from the ED, follow-up can be conducted at any time by telephone.

The goal of informed consent is for a potential research study subject to gain a clear understanding of the purpose of the research and any associated risks, benefits, and alternatives. Obtaining informed consent is a skill that must be taught to all research personnel and involves knowledge of appropriate human subject protections and experience in conducting conversations with patients. We believe that at a minimum, to ensure the integrity of the informed consent process, patients should read the document, ask questions, and desire and be given a copy of the form. Ideally, the process should exceed this minimum and involve some assessment of patient understanding before participation, which should be stratified according to the risks and benefits of a particular study.

The observed behaviors of ED patients in the current study suggest that either the informed consent process may have been suboptimal or that patients may not be interested in all these elements of the informed consent process when they judge the study intervention to be low risk and simple. Slightly more than half of the patients read the form at all, and the majority of these patients spent less than 2 minutes reading a 2-page, 11-paragraph document. In addition, a minority (20%) of patients asked a question about the study, and less than half accepted a copy of the form when it was handed to them. One would assume that most patients would accept papers handed to them in a research setting, and the fact that so many were uninterested in retaining a copy of the form again demonstrates either suboptimal patient engagement in the informed consent process or a process that is not suited to patient desires.

There are several explanations for why our study population displayed such a high rate of uninterest in the informed consent process for the intimate partner violence study. It is possible that many of those who did not read or who spent almost no time reading the consent form were not able to read and were embarrassed to say so. We do not believe this to be the case because, in other more complex studies in our department, patients spend more time engaged in the informed consent process. This study, as well as many other survey studies, involved no more than minimal risk to the participants and this was stated in the consent form. Although patients were asked questions of a personal nature, there were no experimental or invasive interventions. Therefore, it is possible that patients were less concerned about the informed consent process in general because of the perception of the low risk of the study. In addition, the sensitive nature of intimate partner violence may have affected study participants' behavior during the informed consent process such that patients were more guarded in their interactions with the research team and therefore wanted to limit the amount of time they focused on study activities.

Ideally, there should be no difference in the importance attached to the informed consent process whether administered orally or in writing; patients and investigators will likely perceive that written informed consent confers greater importance and gravity to what is being asked. This study was designed to be part of a larger study examining the effect of written informed consent on the detection of intimate partner violence in ED patients. On odd days, patients were approached for participation with verbal informed consent, and on even days they were asked for written informed consent.⁷ Written informed consent was associated with a higher refusal rate than oral informed consent, but use of written informed consent did not result in a lower rate of detection for multiple forms of violence. The higher refusal rate on even days may be related to written informed consent as a deterrent for participation.³⁷ Given that the main outcome (detection of violence in the home) was not affected by the method of informed consent, it could be argued that written informed consent for a survey study adds a dimension of formality that may be nothing more than a formality. The written document may itself elicit a feeling of distrust in a patient and lead to changes in patient behavior in regard to research participation.³⁸ However, in this study the perceived low risk was likely to be more of an influence on patient behavior than the nature of the informed consent. In the situation of a study with perceived low risk, perfectly reasonable behavior may clash with the regulation writers' mental model of “rational man.”

It is incumbent on researchers to provide the best protective measures with regard to ED patients' participation in research. This should begin with the recognition that ED patients in general do not know their health care providers (may have less trust), are subject to physiologic derangements that may affect their decisionmaking, or may be in pain or discomfort related to anxiety or fear of the unknown. Previous studies have consistently found that less educated and elderly populations have a diminished understanding of informed consent information.⁸, ³⁹, ⁴⁰ Our study population was relatively young and non–acutely ill, but other characteristics of these patients that might have affected their vulnerability were not studied and might be mitigating factors in the behaviors associated with informed consent.

In conclusion, ED patients showed little interest in the informed consent process for an intimate partner violence survey study, as demonstrated by low rates of reading the consent form, asking questions about the study, and accepting a copy of the informed consent document. Ways to improve the informed consent process in the ED should be explored and may include the provision of greater training to investigators and research extenders if the goal of informed consent is to be realized. The role of informed consent in survey studies that are considered to be of minimal or no more than minimal risk should also be explored. In such studies, the perceived optimal informed consent behaviors may never be achieved despite interventions designed to improve the process.

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