Carla Black, PhD¹, Katherine Harris, PhD², Jürgen Maurer, PhD², Rosanna Setse, MD, MPH, PhD³ and Gary Euler, DrPH, MPH⁴, 1Immunization Services Division, Centers for Disease Control and Prevention, Atlanta, GA, 2Health Program, RAND Corporation, Arlington, VA, 3Assessment Branch, Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, 4Immunization Services Division- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA