Sample size em edits

[d-morrison]

Thank you for taking the time to submit a pull request!

To maximize the chances of acceptance:

• The title of your PR should briefly describe the change.
• The body of your PR should contain Fixes #issue-number (if relevant).
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• Documentation should use roxygen2, with Markdown syntax.
• Contributions should include unit tests (using testthat).

For more information see Contributing.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅