The STOP-HPV Scale Up Study

Human papillomavirus (HPV) causes 35,900 US cancer cases per year, 4,000 deaths, and $4 billion in can In this study, the investigators will conduct a 3-arm clustered randomized controlled trial (RCT) in an estimated 72 practices from up to 8 health systems to evaluate the effectiveness and cost effectiveness of two potentially scalable implementation strategies (based on prior work) to increase the initiation of HPV vaccine against a usual care (control) arm. The intervention arms are 1) online provider communication training only ("STOP-HPV-Online" and 2) online provider communication training plus a Learning Collaborative, with performance feedback, attended by practice leads ("STOP-HPV-LC).

cer-related costs. It is recommended at ages 11-12 years routinely but can be given starting at ages 9-10 years. Despite having an effective vaccine, HPV vaccine initiation/completion rates in the U.S. were only at 76.8%/61.4% respectively in 2023 among 13-17 year olds; these rates are lower than the other recommended adolescent vaccines. Two key barriers are 1) suboptimal clinician communication to address parental concerns and 2) ineffective office systems causing missed vaccine opportunities.

Study Overview

• Status: Recruiting
• Conditions: Human Papilloma Virus Vaccine
• Intervention / Treatment: Behavioral: STOP-HPV-Online; Behavioral: STOP-HPV-LC

Detailed Description

In prior work, the investigators have tested two implementation strategies/interventions that were effective, but which were deployed by the research team. The first is provider communication training ("STOP-HPV-Online"), delivered by the research team, in a cluster RCT in 48 pediatric practices from a research network (6.8% improvement in initiation). The other is a quality improvement, pre-post study, that included both provider communication training, as well as a Learning Collaborative (LC) for practice leads (8% increase in initiation).

A major challenge in implementation science and spreading practice-based strategies is to move from research teams deploying implementation strategies (intervention) to health systems deploying them. In this study, the investigators will compare the effectiveness and cost-effectiveness of the two implementation strategies (interventions) using a 3-arm clustered RCT: 1) STOP-HPV-Online vs 2) STOP-HPV-LC vs 3) usual care. The study team will randomize an estimated 72 practices (from up to 8 health systems) to the 1) STOP-HPV-Online arm, 2) the STOP-HPV-LC arm or 3) the control arm, assess fidelity to the intervention and conduct the evaluation. A collaborating organization, AMGA (the American Medical Group Association), will facilitate training of the health system personnel, as needed; however, the health systems will deploy each intervention. The primary outcome measure is the initiation rate among 9-<13 year olds with a well-child care visit during the 12 month intervention period (with inclusion starting at the time of a well child care visit during the intervention period). A secondary outcome measure will be the initiation rate among 13-17 year olds with a well child care visit during the intervention period (with inclusion starting at the time of a well child care visit during the intervention period. For both measures, inclusion criteria will be: 1) presenting to a participating practice, 2) age eligible at the visit and 3) no prior vaccine at the time of the visit.

• Study Type: Interventional
• Enrollment (Estimated): 100000
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Peter Szilagyi, MD, MPH; Phone Number: 310-206-6328; Email: pszilagyi@mednet.ucla.edu
• Study Contact Backup: Name: Christina Albertin, PhD, MPH; Phone Number: 317-701-4926; Email: calbertin@mednet.ucla.edu

Study Locations

• United States
  • Virginia
    • Alexandria, Virginia, United States, 22314
      • Recruiting
      • AMGA
      • Contact: Cindy Shekailo; Phone Number: 361 703-838-0033; Email: cshekailo@amga.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patient of participating practice
• Well child care visit during the 12-month intervention period
• No prior dose of HPV vaccine at the time of the well child care visit
• Age-eligible

Exclusion Criteria:

• Prior dose of HPV vaccine

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: STOP-HPV Online; Provider communication training	Behavioral: STOP-HPV-Online; Approximately one third of practices within a participating health system will be randomized to receiving the STOP-HPV-Online intervention.
Experimental: STOP-HPV LC; Provider communication training plus Learning Collaborative sessions attended by practice leads and quarterly performance feedback to the practice.	Behavioral: STOP-HPV-LC; Approximately one third of practices within a participating health system will be randomized to receiving the STOP-HPV-LC intervention.
No Intervention: Usual Care; Standard of care control

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Initiation (first dose) of HPV vaccination among 9-<13 year olds at or following a well care visit with a participating provider during the intervention period.	The percent of children ages 9-<13 years of age who received their first dose of HPV vaccine at or following a well child care visit with a participating provider during the intervention-period (denominator is children ages 9-<13 with a well child visit during the study period at which they were due for their first dose).	12 months from start of intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total implementation cost	The difference in costs between arms will be used to calculate the incremental cost-effectiveness ratio (ICER)	12 months from start of intervention
Initiation (first dose) of HPV vaccination among 13-17 year olds at or following a well care visit with a participating provider during the intervention period.	The percent of children ages 13-17 years of age who received their first dose of HPV vaccine at or following a well child care visit with a participating provider during the intervention-period (denominator is children ages 13-17 years with a well child visit during the study period at which they were due for their first dose).	12 months from start of intervention
Initiation (first dose) of HPV vaccination among 9-<13 year olds at or following a well care visit with any provider during the intervention period.	The percent of children ages 9-<13 years of age who received their first dose of HPV vaccine at or following a well child care visit with any provider (participating or not) during the intervention-period (denominator is children ages 9-<13 with a well child visit during the study period at which they were due for their first dose).	12 months from start of intervention
Initiation (first dose) of HPV vaccination among 13-17 year olds at or following a well care visit with any provider during the intervention period.	The percent of children ages 13-17 years of age who received their first dose of HPV vaccine at or following a well child care visit with any provider (participating or not) during the intervention-period (denominator is children ages 13-17 years with a well child visit during the study period at which they were due for their first dose).	12 months from start of intervention

Collaborators and Investigators

• Sponsor: University of California, Los Angeles
• Collaborators: National Cancer Institute (NCI); American Medical Group Association
• Investigators: Principal Investigator: Peter Szilagyi, MD, MPH, University of California, Los Angeles

Study record dates

Study Major Dates

• Study Start (Actual): March 30, 2026
• Primary Completion (Estimated): April 19, 2027
• Study Completion (Estimated): April 19, 2027

Study Registration Dates

• First Submitted: February 14, 2025
• First Submitted That Met QC Criteria: February 14, 2025
• First Posted (Actual): February 18, 2025

Study Record Updates

• Last Update Posted (Actual): May 19, 2026
• Last Update Submitted That Met QC Criteria: May 18, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Human Papillomavirus Vaccination; Practice-based improvement
• Additional Relevant MeSH Terms: Neoplasms; Neoplasms by Histologic Type; Neoplasms, Glandular and Epithelial; Neoplasms, Squamous Cell; Papilloma
• Other Study ID Numbers: 23-000022; 1R01CA276151-01 (U.S. NIH Grant/Contract)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No