Qualitative analysis of a risk in PRINCE2 assesses, at a minimum, the likelihood of each risk occurring and its potential impact on project objectives. This analysis helps in prioritizing risks based on their severity and likelihood, which is crucial for effective risk management and decision-making about risk responses.
(PRINCE2 7 Foundation Handbook, AXELOS)

When deciding the duration of a management stage in PRINCE2, one key factor is the work packages to be delivered during the stage. The content and complexity of these work packages can significantly influence the length of the stage, as they define the scope and volume of work to be completed before the next stage review.
References: PRINCE2 Foundation Handbook, Tailoring and Adopting PRINCE2 section.

The Quality Register in PRINCE2 should record all quality activities planned and executed to ensure the products are fit for purpose (1), and the roles responsible for reviewing the project's products (4). This register helps in tracking and managing the quality review process effectively.
= PRINCE2 7 Foundation handbook and online resources

The Senior User within the PRINCE2 project management team represents the interests of those who will use the project's products and benefit from their operation after the project is complete. This role is responsible for specifying the needs of users, ensuring the solution meets these needs, and is capable of delivering the anticipated benefits. References: PRINCE2 Foundation manual, PRINCE2 official resources

The purpose of a Project Brief in PRINCE2 is to provide a solid basis for the initiation of the project. The Project Brief includes the outline of the project's objectives, scope, constraints, and assumptions. It is developed during the 'Starting up a Project' process and is used to ensure that a clear, concise, and feasible plan is proposed before the project is formally initiated.
PRINCE2 7 Foundation resources and materials.