Study concept and design: Omer, Hinman, Orenstein.
Acquisition of data: Omer, Peterson.
Analysis and interpretation of data: Omer, Curran, Hinman, Orenstein.
Drafting of the manuscript: Omer, Curran.
Critical revision of the manuscript for important intellectual content: Omer, Peterson, Curran, Hinman, Orenstein.
Statistical analysis: Curran.
Administrative, technical, and material support: Omer, Orenstein.
Study supervision: Omer.
Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Hinman reported receiving institutional grant funding from the US Centers for Disease Control and Prevention, the Bill & Melinda Gates Foundation, Novartis Vaccines, and the Merck Company Foundation. No other disclosures were reported.
Additional Contributions: We thank Christine Finley, MPH (Vermont Department of Public Health), Catherine Martin, BS (California Immunization Coalition), and Daniel A. Salmon, PhD (Johns Hopkins University Bloomberg School of Public Health), for their input. None received compensation for their contribution.