We examined parents' reported changes in vaccination of their children <7 years.
Vaccine acceptance and intentional delay remained stable between 2012 and 2014.
Regional differences in acceptance, delay, and refusal were detected over time.
Between 2012 and 2014 vaccine refusal decreased among parents of children 2–6 years.
Parents were most certain of their refusal of MMR and chickenpox compared to other vaccines.