HPV Multilevel Intervention Strategies Targeting Immunization in Community Settings (HPV MISTICS): Study protocol for a hybrid 1 stepped-wedge cluster randomized trial.

Background: This protocol paper describes the overall design for HPV MISTICS, a multilevel intervention to increase human papillomavirus (HPV) vaccination initiation and completion rates among adolescents aged 11-17.

Methods: We will conduct a hybrid type 1 implementation-effectiveness trial using a stepped-wedge cluster randomized trial in eight federally qualified health centers (FQHCs) in Florida. Intervention components target three levels: system, providers, and parents.