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Interventions to reduce vaccine hesitancy among adolescents: a cluster-randomized trial

Nature Human Behaviour volume 10, pages 92–100 (2026)Cite this article

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Abstract

School interventions targeting adolescents’ general knowledge of vaccination are rare despite their potential to reduce vaccine hesitancy. This cluster-randomized trial involving 8,589 French ninth graders from 399 schools tests two interventions against the standard curriculum. The first provided teachers with ready-to-use pedagogical activities, while the second used a chatbot. Both interventions significantly improved adolescents’ attitudes towards vaccination, the primary outcome of this trial (Pedagogical Activities: t398 = 2.99; P = 0.003; β = 0.094; 95% confidence interval (CI), (0.032, 0.156); Chatbot: t398 = 2.07; P = 0.039; β = 0.063; 95% CI, (0.003, 0.124)). Both also improved pupils’ knowledge of vaccination (Pedagogical Activities: t398 = 3.23; P = 0.0013; β = 0.103; 95% CI, (0.040, 0.165); Chatbot: t398 = 2.23; P = 0.027; β = 0.070; 95% CI, (0.008, 0.132)). That such interventions can improve pupils’ acceptance and understanding of vaccines has important consequences for public health.

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Fig. 1: Trial profile.

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Data availability

The preregistration for this study, as well as pupils’ and teachers’ anonymized answers to all questionnaires, are available via this study’s OSF repository at https://osf.io/rf5w9/?view_only=de759e4e36914c909adeac5fd541babf. The demographic data used in the secondary models cannot be shared, as per our agreement with the French Ministry of Education. To access the relevant databases (SYSCA 2022–2023, ARCHIPEL 2022–2023 and Evaluations nationales à l’entrée en 6e: 2018–2019 and 2019–2020), students and members of research organizations can submit a request to the French Ministry of Education to obtain an agreement with the Direction de l’Évaluation, de la Prospective et de la Performance. This request needs to be submitted in French and should include the composition of the research team involved in the project, a list of the requested information, a description of the analysis methodology and the research question it aims at answering. Requests should be sent to depp_recherche@education.gouv.fr. More information can be obtained by contacting the information centre of the department at depp.documentation@education.gouv.fr.

Code availability

The code used to allocate schools to experimental groups and conduct all analyses reported here can be found via this study’s OSF repository at https://osf.io/rf5w9/?view_only=de759e4e36914c909adeac5fd541babf.

References

  1. Watson, O. J. et al. Global impact of the first year of COVID-19 vaccination: a mathematical modelling study. Lancet Infect. Dis. 22, 1293–1302 (2022).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  2. Figueiredo, Ade, Simas, C., Karafillakis, E., Paterson, P. & Larson, H. J. Mapping global trends in vaccine confidence and investigating barriers to vaccine uptake: a large-scale retrospective temporal modelling study. Lancet 396, 898–908 (2020).

    Article  PubMed  PubMed Central  Google Scholar 

  3. Wallace, J., Goldsmith-Pinkham, P. & Schwartz, J. L. Excess Death Rates for Republicans and Democrats During the COVID-19 Pandemic Working Paper No. 30512 (National Bureau of Economic Research, 2022).

  4. Jarrett, C., Wilson, R., O’Leary, M., Eckersberger, E. & Larson, H. J. Strategies for addressing vaccine hesitancy—a systematic review. Vaccine 33, 4180–4190 (2015).

    Article  PubMed  Google Scholar 

  5. Kaufman, J. et al. Face-to-face interventions for informing or educating parents about early childhood vaccination. Cochrane Database Syst. Rev. 5, CD010038 (2018).

    PubMed  Google Scholar 

  6. Cadeddu, C. et al. Understanding the determinants of vaccine hesitancy and vaccine confidence among adolescents: a systematic review. Hum. Vaccines Immunother. 17, 4470–4486 (2021).

    Article  Google Scholar 

  7. Maisonneuve, A. R., Witteman, H. O., Brehaut, J., Dubé, È. & Wilson, K. Educating children and adolescents about vaccines: a review of current literature. Expert Rev. Vaccines 17, 311–321 (2018).

    Article  CAS  PubMed  Google Scholar 

  8. Wellcome Global Monitor: How Does the World Feel About Science and Health? (Wellcome Global Monitor, 2018); https://wellcome.org/reports/wellcome-global-monitor/2018

  9. Algan, Y., Cohen, D., Davoine, E., Foucault, M. & Stantcheva, S. Trust in scientists in times of pandemic: panel evidence from 12 countries. Proc. Natl Acad. Sci. USA 118, e2108576118 (2021).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Konstantinou, P. et al. Transmission of vaccination attitudes and uptake based on social contagion theory: a scoping review. Vaccines 9, 607 (2021).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Glik, D. et al. Impact of an immunization education program on middle school adolescents. Am. J. Health Behav. 28, 487–497 (2004).

    Article  PubMed  Google Scholar 

  12. Principi, N. & Esposito, S. Adolescents and vaccines in the western world. Vaccine 31, 5366–5374 (2013).

    Article  PubMed  Google Scholar 

  13. Attwell, K. & Smith, D. T. Parenting as politics: social identity theory and vaccine hesitant communities. Int. J. Health Gov. 22, 183–198 (2017).

    Google Scholar 

  14. Askelson, N. M. et al. Implementation challenges and opportunities related to HPV vaccination quality improvement in primary care clinics in a rural state. J. Community Health 44, 790–795 (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  15. Reiter, P. L., Gilkey, M. B. & Brewer, N. T. HPV vaccination among adolescent males: results from the National Immunization Survey-Teen. Vaccine 31, 2816–2821 (2013).

    Article  PubMed  PubMed Central  Google Scholar 

  16. Grandahl, M. et al. School-based intervention for the prevention of HPV among adolescents: a cluster randomised controlled study. BMJ Open 6, e009875 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  17. Cates, J. R., Diehl, S. J., Crandell, J. L. & Coyne-Beasley, T. Intervention effects from a social marketing campaign to promote HPV vaccination in preteen boys. Vaccine 32, 4171–4178 (2014).

    Article  PubMed  PubMed Central  Google Scholar 

  18. Abdullahi, L. H., Kagina, B. M., Ndze, V. N., Hussey, G. D. & Wiysonge, C. S. Improving vaccination uptake among adolescents. Cochrane Database Syst. Rev. 1, CD011895 (2020).

    PubMed  Google Scholar 

  19. Siddiqui, F. A. et al. Interventions to improve immunization coverage among children and adolescents: a meta-analysis. Pediatrics 149, e2021053852D (2022).

    Article  PubMed  Google Scholar 

  20. Skinner, S. R. et al. Randomised controlled trial of an educational strategy to increase school-based adolescent hepatitis B vaccination. Aust. N. Z. J. Public Health 24, 298–304 (2000).

    Article  CAS  PubMed  Google Scholar 

  21. O’Mahony, M. C. & Begg, N. Rubella vaccination: the effect of health education and administrative systems on vaccination rates in two health authorities. Public Health 100, 84–90 (1986).

    Article  PubMed  Google Scholar 

  22. Underwood, N. L. et al. Evaluation of educational interventions to enhance adolescent specific vaccination coverage. J. Sch. Health 89, 603–611 (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  23. Esposito, S. et al. Impact of a website based educational program for increasing vaccination coverage among adolescents. Hum. Vaccin. Immunother. 14, 961–968 (2018).

    Article  PubMed  PubMed Central  Google Scholar 

  24. Bethke, N. et al. Increasing vaccinations through an on-site school-based education and vaccination program: a city-wide cluster randomized controlled trial. Appl. Psychol. Health Well Being 16, 1326–1348 (2024).

    Article  PubMed  Google Scholar 

  25. Lazonder, A. W. & Harmsen, R. Meta-analysis of inquiry-based learning: effects of guidance. Rev. Educ. Res. 86, 681–718 (2016).

    Article  Google Scholar 

  26. Mercier, H. & Sperber, D. The Enigma of Reason (Harvard Univ. Press, 2018); https://doi.org/10.4159/9780674977860

  27. Chanel, O., Luchini, S., Massoni, S. & Vergnaud, J.-C. Impact of information on intentions to vaccinate in a potential epidemic: swine-origin influenza A (H1N1). Soc. Sci. Med. 72, 142–148 (2011).

    Article  PubMed  Google Scholar 

  28. Altay, S., Hacquin, A.-S., Chevallier, C. & Mercier, H. Information delivered by a chatbot has a positive impact on COVID-19 vaccines attitudes and intentions. J. Exp. Psychol. Appl. 29, 52–62 (2023).

    Article  PubMed  Google Scholar 

  29. Altay, S. et al. Scaling up interactive argumentation by providing counterarguments with a chatbot. Nat. Hum. Behav. 6, 579–592 (2022).

    Article  PubMed  Google Scholar 

  30. Kang, M. J. et al. The wick in the candle of learning: epistemic curiosity activates reward circuitry and enhances memory. Psychol. Sci. 20, 963–973 (2009).

    Article  PubMed  Google Scholar 

  31. Fastrich, G. M., Kerr, T., Castel, A. D. & Murayama, K. The role of interest in memory for trivia questions: an investigation with a large-scale database. Motiv. Sci. 4, 227–250 (2018).

    Article  PubMed  Google Scholar 

  32. Zingg, A. & Siegrist, M. Measuring people’s knowledge about vaccination: developing a one-dimensional scale. Vaccine 30, 3771–3777 (2012).

    Article  PubMed  Google Scholar 

  33. Kline, R. B. Principles and Practice of Structural Equation Modeling (Guilford, 2023).

  34. Hu, L. & Bentler, P. M. Cutoff criteria for fit indexes in covariance structure analysis: conventional criteria versus new alternatives. Struct. Equ. Modeling 6, 1–55 (1999).

    Article  Google Scholar 

  35. Nyhan, B. & Reifler, J. Does correcting myths about the flu vaccine work? An experimental evaluation of the effects of corrective information. Vaccine 33, 459–464 (2015).

    Article  PubMed  Google Scholar 

  36. Coppock, A. Persuasion in Parallel: How Information Changes Minds About Politics (Univ. Chicago Press, 2023).

  37. Xu, H. G. et al. Personalized dialogues with AI effectively address parents’ concerns about HPV vaccination. Preprint at https://osf.io/gv52j/download (2025).

  38. Costello, T. H., Pennycook, G. & Rand, D. G. Durably reducing conspiracy beliefs through dialogues with AI. Science 385, eadq1814 (2024).

    Article  CAS  PubMed  Google Scholar 

  39. Czarnek, G. et al. Addressing climate change skepticism and inaction using human–AI dialogues. Preprint at psyArxiv https://doi.org/10.31234/osf.io/mqcwj_v1 (2025).

  40. Programme du Cycle 4 en Vigueur à la Rentrée 2020 (Ministère de l'Education Nationale, de l'Enseignement Supérieur et de la Recherche, 2020).

  41. R Core Team R: A language and environment for statistical computing (R Foundation for Statistical Computing, 2022); https://www.R-project.org/

  42. Berge L. Efficient Estimation of Maximum Likelihood Models with Multiple Fixed-Effects: the R package FENmlm. CREA Discussion Papers 18–13 (University of Luxembourg, 2018).

  43. Rosseel, Y. lavaan: an R package for structural equation modeling. J. Stat. Softw. 48, 1–36 (2012).

    Article  Google Scholar 

  44. Friedman, J., Hastie, T. & Tibshirani, R. Regularization paths for generalized linear models via coordinate descent. J. Stat. Softw. 33, 1–22 (2010).

    Article  PubMed  PubMed Central  Google Scholar 

  45. Ben-Shachar, M. S., Lüdecke, D. & Makowski, D. effectsize: Estimation of effect size indices and standardized parameters. J.Open Source Softw. 5, 2815 (2020).

    Article  Google Scholar 

  46. Équipe Évaluation exhaustive sixième, DEPP-B2-1 et B2-2. Évaluation Exhaustive de Début de Sixième 2023: des Performances en Légère Hausse Depuis 2017, y Compris en REP+ (Ministère de l’Education Nationale, de l’Enseignement Supérieur et de la Recherche, 2024); https://www.education.gouv.fr/evaluation-exhaustive-de-debut-de-sixieme-2023-des-performances-en-legere-hausse-depuis-2017-y-414234

Download references

Acknowledgements

The availability of the MENJ-DEPP data was made possible by the Innovations, Données et Expérimentations en Éducation project, funded by the Agence Nationale de la Recherche as part of the ‘Investissements d’avenir’ programme (reference no. ANR-21-ESRE-0034). This study was supported by the EUR FrontCog grants ANR-17-EURE-0017 and ANR-10-IDEX-0001-02 awarded to Université PSL, by the France 2030 grant ANR-23-IAHU-0006 awarded to the Women’s Cancers Institute, and by the ANR-21-SSMS-0006, and ANR-21-CE28-0016-01 grants awarded to H.M. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.

Author information

Author notes

  1. These authors contributed equally: C. Chevallier, H. Mercier.

Authors and Affiliations

  1. Institut Jean Nicod, Département d’Études Cognitives, École Normale Supérieure, Université PSL, EHESS, CNRS, Paris, France

    N. Baudouin, S. de Rouilhan, E. Pasquinelli, C. Chevallier & H. Mercier

  2. LEDa, Université Paris-Dauphine, Université PSL, IRD, CNRS, Paris, France

    E. Huillery

  3. Fondation La Main à la Pâte, Paris, France

    E. Pasquinelli

  4. Women’s Cancers Institute, Institut Curie, Paris, France

    C. Chevallier

Authors
  1. N. Baudouin
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  2. S. de Rouilhan
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  3. E. Huillery
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  4. E. Pasquinelli
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  6. H. Mercier
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Contributions

C.C. and H.M. contributed equally to this work. C.C., E.P., H.M. and N.B. created the material for the intervention. N.B. carried out the analysis under the supervision of C.C., E.H. and H.M. S.d.R. generated the random allocation sequence and oversaw the school enrolment process and data collection. All authors interpreted the data and contributed to the discussion. All authors contributed to the writing of the final manuscript and revised it critically. C.C. and H.M. are the guarantors of this work and, as such, had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. All authors read and approved the final manuscript. The analyses and interpretations presented here are the sole responsibility of the authors.

Corresponding authors

Correspondence to C. Chevallier or H. Mercier.

Ethics declarations

Competing interests

At the time of submission, E.P. was employed by La Main à la Pâte, the non-governmental organization that created the materials in the Pedagogical Activities condition. The other authors declare no competing interests.

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Nature Human Behaviour thanks Dongqing Wang, Jeremy Ward and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.

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Supplementary Sections 1–4, Tables 1–6 and Fig. 1.

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Baudouin, N., de Rouilhan, S., Huillery, E. et al. Interventions to reduce vaccine hesitancy among adolescents: a cluster-randomized trial. Nat Hum Behav 10, 92–100 (2026). https://doi.org/10.1038/s41562-025-02306-2

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