Conception and design: Ames. Acquisition of data: Lafage. Analysis and interpretation of data: Oh, Scheer, Ames. Drafting the article: Oh, Scheer. Critically revising the article: Oh, Scheer, Eastlack, Smith, Lafage, Bess, Schwab, Ames. Reviewed submitted version of manuscript: all authors. Approved the final version of the manuscript on behalf of all authors: Oh. Statistical analysis: Oh. Study supervision: Ames.