If disclosure of a subject's involvement in a specific research study can be potentially harmful, what is the best course of action regarding informed consent?

Obtaining a waiver of documentation of informed consent is appropriate when disclosure of a subject's involvement in a research study could harm them. This option allows researchers to proceed with their study without needing to document the subjects’ consent formally, thus minimizing the potential risk associated with that disclosure.

In scenarios where participants could face negative consequences if their participation becomes known—such as stigma, legal repercussions, or privacy violations—waiving the requirement for written consent serves to protect them. This approach is particularly useful in sensitive studies, allowing research to continue while maintaining ethical standards and participant confidentiality.

The other options may not adequately address the specific risks associated with harmful disclosures. Ensuring all subjects are aware of their participation could inadvertently heighten exposure to harm, while increasing participant compensation does not necessarily mitigate the risk of disclosure. Limiting the duration of the study might reduce exposure time but does not remove the potential for harm if identification occurs. Hence, obtaining a waiver of documentation stands out as the most effective and ethical course of action in such cases.