In 1995, the Immunization Practices Advisory Committee (ACIP), American Academy of Pediatrics, and the American Association of Family Physicians issued the first “harmonized” childhood immunization schedule, combining recommendations of all three national groups.

In the 50 years since inception of ACIP, the number of vaccines included in the recommended child/adolescent immunization schedule (for persons aged 0 through 18 years) has increased from vaccines targeting six vaccine-preventable diseases to vaccines for the prevention of 16 such diseases, and the recommended immunization schedule for adults (persons aged ≥19 years) includes vaccines targeting 15 vaccine-preventable diseases

Enactment of the Vaccines for Children (VFC) program in 1993 gave ACIP a new role. VFC provides an entitlement to free vaccine for all children aged 0 through 18 years who are uninsured, Medicaid eligible, American Indian/Alaska Native, or underinsured who receive vaccines at a federally qualified health center or rural health clinic; approximately 50% of U.S. children aged 0 through 18 years are VFC-eligible. If ACIP recommends that a vaccine be administered routinely to children, ACIP is then empowered to declare that the vaccine will be included in VFC.

Another shift in ACIP’s approach to development of vaccine policy occurred in 2010, when the Committee voted to adopt the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to enhance transparency, continuity, and communication, and make explicit the quality of evidence reviewed.

ACIP systematically assesses the type and quality of evidence about a vaccine’s expected health impacts and the balance of health benefits and risks, along with the values and preferences of persons affected. Evidence is grouped into four categories, with the order reflecting the level of confidence in the estimated effect of vaccination on health outcomes. Data tables used for development of ACIP vaccine recommendations are posted on the ACIP website.