Pengjun Lu, PhD, Immunization Services Division, Centers for Disease & Prevention, Atlanta, GA, David B. Callahan, MD, CDC, Helen Ding, MD, MSPH, Assessment Branch, Immunization Service Division, NCIRD, Chenega Government Consulting LLC, Atlanta, GA and Gary Euler, DrPH, MPH, Immunization Services Division- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA