January 25, 2005

Informed Consent in Schizophrenia

Wirshing DA, Sergi MJ, Mintz J.
A videotape intervention to enhance the informed consent process for medical and psychiatric treatment research.
Am J Psychiatry. 2005 Jan;162(1):186-8.

Informed consent: assessment of comprehension.
Am J Psychiatry. 1998 Nov;155(11):1508-11.

The topic of informed consent can be difficult when conducting research, particularly when mental illness is involved. The process often involves explaining complex and technical procedures to an audience who otherwise would not have knowledge of such. A skilled clinician must know how to address concerns and explain difficult concepts in language appropriate to the patient/subject. Legal requirements often add more risks than might otherwise be discussed and so it can be difficult to convey the seriousness of such risks. True informed consent is a legal definition that is usually considered to have occurred if the patient is able to have the ability to express a choice, understand the risks/benefits/alternatives to proposed treatment, appreciate the significance of the choice have or forego treatment, and to come to their decision in a rational manner.

Psychiatric patients often are considered to have difficulties in the latter part of the consent process. There are some who maintain that those with delusions or hallucinations are unable to come to rational decisions. Those who work more closely with patients who have those symptoms may disagree, but nevertheless the bias is often present. While psychiatry patients are often considered to have extra difficulties in understanding consents, it is the case that patients from a broad spectrum of disease have similar problems in understanding the complexities of modern medicine. In one survey, it was found that 60% of cancer patients could not describe even one benefit or risk as little as one day after signing a consent form for chemotherapy.

In article 1, the authors describe an experimental videotape that they made to assist in teaching patients prior to going through an informed consent process. It included explanations regarding their rights and carefully explained the process of obtaining an informed consent. Additionally, it gave examples of how patients can be active participants in the consent process, and ways that they can take the information they’ve been given to make a good decision for them. They compared patients with schizophrenia to patients with other medical disorders and to healthy university students. Patients were randomly assigned either to watch the experimental videotape or to watch a similar tape that was written with an identical tone but was an historical piece about human subject research.

The groups started with different levels of pretest knowledge. The VA medical patients scored the highest on the pretest and the schizophrenia patients the lowest. However, all groups showed a significant learning when given the experimental tape versus the historical tape. The university students had the highest gains on the post-test, but all groups showed some benefit. Schizophrenia patients who demonstrated problems with conceptual organization type of thinking tended to score the worst on the pre/post test. However, other symptoms such as hallucinations or delusions did not have any correlation with their ability on the pre or post test. It should be noted though, that the most psychotic people were generally screened out from participating in this research as they would be unlikely research candidates for other studies. However, the population studied is generally the population that will enroll in a long term study and therefore this tape may have some utility with that group of individuals.

Article 2 describes research in which they determined whether patients with schizophrenia had the ability to understand the concepts involved in informed consent. They looked at patients who were being enrolled in other studies at the VA as they were going through the consent process. Patients were given a quiz in which the main concepts of informed consent were tested. If they did not answer all questions correctly the first time, they took the quiz again until they got all the answers correct. Only after answering the questions correctly could they sign the informed consent. One week later the test was readministered and again they had to answer all questions correctly in order to participate in research. It was seen that 37% of the subjects needed 3 or more trials to pass the test completely. Again, it was conceptual disorganization, more than hallucinations or delusions, that correlated with ability to perform on the test.

Overall, these studies demonstrate that the ability to perform thorough informed consenting is challengign for physician and patient alike. There is evidence that particular symptoms, namely conceptual disorganization, make consent more difficult for schizophrenia patients than healthy people. However, symptoms such as hallucinations or delusions do not seem to impact strongly a patient's ability to understand risks and benefits and to make rational decisions regarding their treatment, particuarly if given adequate support during the consenting process.

Click here for article 1 on pubmed
Click here for article 2 on pubmed

Author: Jacob


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