Measuring school level attributable risk to support school-based HPV vaccination programs

Area of Science:

• Public Health
• Epidemiology
• Adolescent Health

Background:

• High HPV vaccine uptake in Australian 15-year-olds (89% females, 86% males in 2017).
• Significant variation in HPV vaccination initiation rates exists between schools.
• Understanding school-level factors is crucial for addressing disparities in HPV vaccination.

Purpose of the Study:

• To identify school-level characteristics associated with lower HPV vaccination initiation.
• To quantify the contribution of these factors to between-school variation in HPV vaccination uptake.

Main Methods:

• Population-based ecological analysis using school-level data from three Australian jurisdictions (2016).
• Logistic regression models to assess factors linked to low initiation (<75% first dose).
• Estimation of population attributable risk (PAR) and school-level prevalence for identified factors.

Main Results:

• Factors associated with lower initiation include: small school size (OR=9.3), special education schools (OR=5.6), higher Indigenous enrollment (OR=2.7), lower attendance (OR=2.6), remote location (OR=2.6), and lower socioeconomic status (OR=1.8).
• Highest PARs were for small schools (79%), higher Indigenous enrollments (38%), and lower attendance rates (37%).

Conclusions:

• Initiatives targeting smaller schools, those with higher Indigenous student populations, and lower attendance rates are most likely to reduce HPV vaccination uptake variation.
• School-level analysis is valuable for informing policy and resource allocation for school-based vaccination programs.