- Background
- Exclusion from Study or Use of Surrogate Consent
- Decisional Capacity Assessment for Research and Flowchart
Background
Some studies propose to involve subjects whose capacity to make meaningful decisions is in question because they are "cognitively impaired.“ Such subjects may include mentally disabled persons, and those with diagnosed psychoses, Alzheimer's disease or other cognitive disorders — permanent or temporary. Other subjects may have cognitive impairments as a consequence of severe pain, anxiety or confusion, such as individuals with trauma, cancer or life-threatening illness.
Since many people with these conditions retain the capacity to consent to research, not allowing them to consent for themselves when able could compromise their rights.
Federal regulations, California state code, and UC policy indicate that research studies may involve subjects who have cognitive impairments if adequate safeguards are in place. Individuals signing valid research consent forms for themselves must have adequate decisional capacity, but the relevant regulatory documents do not say how capacity should be determined.
The IRB will consider the following principles:
- Studies should not arbitrarily exclude cognitively impaired subjects if they might be able to give informed consent and there is a chance they could benefit from participation.
- Studies involving subjects with cognitive impairment can only be approved if justified and appropriate additional safeguards are in place. Higher risk studies need a higher level of safeguards.
- The primary additional safeguard for this vulnerable subject population is assessment of decisional capacity.
- If adequate decisional capacity is not found upon assessment, the investigator usually needs to either exclude the prospective subject from the study or seek surrogate consent for their participation.
Exclusion from Study or Use of Surrogate Consent
A key choice in study design is whether to 1) exclude people who cannot consent for themselves or 2) include them with surrogate consent from the subject's legally authorized representative.
Note: You must regard a prospective subject's objection or resistance to study participation — in any way or at any time — as a refusal or withdrawal and honor this request immediately, even if a surrogate or the study investigator disagrees with the decision.
Decisional Capacity Assessment for Research
No single set of standards for defining and implementing assessment of decisional capacity has received universal acceptance by experts in the field.
Per UCOP guidance, investigators should "assess subjects on their abilities to understand and to express a reasoned choice concerning the:
- Nature of the research and the information relevant to his/her participation;
- Consequences of participation for the subject’s own situation, especially concerning the subject’s health condition; and
- Consequences of the alternatives to participation. [Applebaum, PS and T. Grisso. "MacCA T-CR: MacAtihur Competence Assessment Tool for Clinical Research. Professional Resource Press, 20QI]"
You should specify who will conduct the decisional capacity assessment, the method(s) of assessment and criteria for identifying incapable subjects. Use the info below to formulate your plan to assess decisional capacity. A less formal procedure to assess potential subjects’ capacity may be permitted if a formal assessment is not feasible or necessary.