The best way to communicate the results of an impact analysis and a change approval to the project sponsor is to present the requirements at a high-level. This means that the BA should provide a summary of the main changes, the rationale behind them, the expected benefits and costs, and the impact on the solution scope and quality. A high-level presentation can be done verbally or in writing, depending on the preference and availability of the project sponsor. A high-level presentation is different from scheduling a requirements workshop, which is a technique to elicit, analyze, or validate requirements with a group of stakeholders; emailing the requirements package, which is a document that organizes and presents the requirements for a specific purpose, audience, or time frame; and creating use case scenarios, which are examples of how the solution will be used by the actors to achieve their goals. Reference:
CCBA Handbook, page 17
[BABOK Guide], page 50
[Business Analysis for Practitioners: A Practice Guide], page 59
[Business Analysis: The Question and Answer Book], page 29