'You know, it feels like you can trust them': mixed methods implementation research to inform the scale up of a health disparities-responsive COVID-19 school testing program

Abstract Background Health disparities lead to negative COVID-19 outcomes for Hispanic/Latino communities. Rapid antigen testing was an important mitigation tool for protecting schools and their communities as in-person learning resumed. Within the context of a 3-middle-school non-inferiority trial we assessed acceptability and appropriateness of at-home and school-based COVID-19 antigen testing and implementation barriers and facilitators to facilitate district-wide scale up. Methods Guided by the Consolidated Framework for Implementation Research (CFIR) and acceptability and appropriateness implementation outcomes, we collected post-implementation qualitative (n = 30) and quantitative (n = 454) data in English and Spanish from trial participants, in-depth feedback sessions among program implementers (n = 19) and coded 137 project meeting minutes. Verbatim transcripts were thematically analyzed. We used multivariate linear models to evaluate program acceptability and appropriateness by COVID-19 testing modality and mixed qualitative and quantitative findings for interpretation. Results Questionnaire respondents closely matched school demographics (> 80% Hispanic/Latino and 8% Filipino/Asian Pacific Islander). While both testing modalities were rated as highly acceptable and appropriate, at-home testing was consistently favorable. Qualitative findings provided actionable areas for at-home testing program refinement, guiding district-wide scale up including: maintaining a learning climate to accommodate modifications as guidelines changed, needs of the school community, and implementation challenges; ensuring an engaged school leadership and sufficient human resources; improving educational communication about COVID-19 and technology ease of use; and increased time for pre-implementation planning and engagement. Conclusions Results underscore the value of the CFIR to inform program implementation, particularly programs to reduce disparities during a public health emergency. Results support optimal testing implementation strategies centering the needs and perspectives of Hispanic/Latinos.