Trust in health workers and patient-centeredness of care were strongest factors associated with vaccination for Kenyan children born between 2017–2022

Objective: Although vaccination confidence is declining globally, there is little detailed information from low- and middle-income countries about factors influencing routine vaccination behavior in these contexts. Methods: In mid-2022, we surveyed people who gave birth in Kenya between 2017–2022, and asked them about their children's vaccination history and about hypothesized correlates of vaccination per the Behavioural and Social Drivers of Vaccination model. Results: Of 873 children in this sample, 117 (13%) were under-vaccinated (i.e., delayed or missing vaccine dose(s)) – and under-vaccination was more common among births during the COVID-19 pandemic (2020–2022) versus pre-pandemic (2017–2019). In multi-level multivariable models, children of respondents who expressed concerns about serious side effects from vaccines had significantly higher odds of missed vaccine dose(s) (aOR 2.06, 95 % CI 1.14–3.72), and there was a strong association between having more safety concerns now versus before the COVID-19 pandemic (aOR missed dose(s) 4.44, 95 % CI 1.71–11.51; aOR under-vaccination 3.03, 95 % CI 1.28–7.19). People with greater trust in health workers had lower odds of having a child with missed vaccine dose(s) (aOR 0.85, 95 % CI 0.75–0.97). People who reported higher patient-centered quality of vaccination care had much lower odds of having children with delayed or missed vaccine dose(s) (aOR missed dose(s) 0.14, 95 % CI 0.04–0.58; aOR under-vaccination 0.27, 95 % CI 0.10–0.79). Conclusions: These findings highlight potential strategies to improve vaccine coverage: greater focus on patient-centered quality of care, training healthcare workers on how to address safety concerns about vaccines, and building trust in the health care system and in health workers.