How Immunization Information Systems Inform Age-Based HPV Vaccination Recommendations in the United States: A Mixed-Methods Study.

: Immunization information systems (IISs) in the United States forecast vaccine due dates, which can inform when providers recommend vaccines to patients. IIS forecasting for HPV vaccination at 9 years, the minimum age of licensure, and when vaccination is likely most effective is not documented or well-understood. : We documented characteristics of HPV vaccination forecasts in jurisdictional IISs through Internet searches and requests to immunization program managers. Next, we conducted focus groups with stakeholders from seven jurisdictions to elucidate their processes for determining and implementing HPV vaccination forecasts. : Forecast data were available from 49 out of 64 CDC-funded jurisdictions, of which 14 (29%) recommended HPV vaccination at age 9 and 35 (71%) recommended HPV vaccination starting at ages 11 through to 15. Jurisdictions that recommended HPV vaccination at age 9 cited the positions of the American Cancer Society and American Academy of Pediatrics and reported little or no provider opposition to this recommendation. Jurisdictions reported variable flexibility in programming their forecasts. Those that changed their HPV vaccination forecast from 11 to 9 years did so easily while some experienced limitations. Other jurisdictions adhered strictly to the CDC's routine recommendation at age 11-12 years and would only update the forecast in tandem with updated CDC guidance. The impact of IISs and electronic health record interoperability on how providers view and utilize IIS forecasting is unclear. : Jurisdictions can share best practices for forecasting at 9 and future studies can evaluate the effects of forecasting age on the vaccination rates, providing evidence for nationwide vaccination recommendations.