Which document serves to protect trial information until public posting?

The correct choice is that placeholder abstracts serve to protect trial information until public posting. Placeholder abstracts are preliminary summaries that are often used to convey essential details about a clinical trial without disclosing complete findings or sensitive information prematurely. This allows researchers to ensure that relevant trial data is shared in accordance with regulatory requirements and timelines while maintaining confidentiality prior to formal publication.

The other document types mentioned do not specifically focus on the protection of trial information in the same context. Patient consent forms are primarily about ensuring that participants are informed about the study and give their permission to participate. Confidentiality agreements relate to the protection of proprietary or sensitive information between parties, but they do not inherently provide a mechanism for managing trial data prior to its public posting. Preliminary reports, on the other hand, may contain more detailed information about the trial’s findings but do not function as placeholders to control the flow of information prior to public disclosure.