Author Contributions: Ms Jensen had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Gärtner, Nielsen, Kroman, Kehlet.
Acquisition of data: Gärtner, Jensen, Nielsen.
Analysis and interpretation of data: Gärtner, Jensen, Ewertz, Kroman, Kehlet.
Drafting of the manuscript: Gärtner, Jensen, Ewertz, Kehlet.
Critical revision of the manuscript for important intellectual content: Jensen, Nielsen, Ewertz, Kroman, Kehlet.
Statistical analysis: Jensen.
Obtained funding: Gärtner, Kroman, Kehlet.
Administrative, technical, or material support: Gärtner, Jensen, Nielsen, Kroman.
Study supervision: Ewertz, Kroman.
Financial Disclosures: None reported.
Funding/Support: This work was supported by grants from the Danish Cancer Society, Breast Friends, and the Lundbeck Foundation. The grants exclusively covered salaries.
Role of the Sponsors: The funding sources played no role in the design or conduct of the study; in the collection, management, analysis, or interpretation of the data; or in the preparation, review, or approval of the manuscript.