When should the sponsor-monitor conduct the most detailed review of the study protocol with the site's study staff?

The sponsor-monitor should conduct the most detailed review of the study protocol with the site's study staff during the site initiation visit. This visit is specifically designed to ensure that all study protocols, procedures, and expectations are clearly communicated and understood by the site staff before the study begins.

During the site initiation visit, the monitor reviews the study's objectives, procedures, and responsibilities in detail, allowing the staff to ask questions and clarify any uncertainties about the protocol. It is a critical phase where training on the protocol and informed consent processes occurs, ensuring that everyone involved is on the same page and prepared to implement the study correctly.

In contrast, although other stages like the prestudy site visit, post-study visit, or periodic monitoring visits involve discussions regarding the study, they do not offer the same level of detailed protocol review and training as the site initiation visit. The prestudy visit typically focuses on feasibility and site readiness but not the detailed protocol walk-through. Post-study visits are more about closing out the trial, and periodic monitoring visits focus on ongoing data collection and compliance rather than in-depth protocol review.