Within the Reports component of Settings, there is a section called "Email templates" where you can customize the emails that are sent out with reports.
If you are an administrator or account owner, this can be accessed through Settings > Reports.
Multiple templates can be created that are more tailored to your organization, and a specific template can be chosen for each scheduled report.
IMPORTANT: The customized email templates DO NOT relate to the default reports sent for Quality Assurance. They are only available when scheduling reports through the Reports component.