The Vaccine Trust Framework: mixed-method development of a tool for understanding and quantifying trust in health systems and vaccines

Abstract

<div> <b><font color="red">Summary</font></b><br> <b>Trust</b> is a key component of vaccine demand; however, there is <b><font color="red">no consensus</font></b> on how to define trust and a <b><font color="red">lack of actionable, contextually grounded measurement tools</font></b> validated in low-income and middle-income countries. </div>

<br>

<div> <b><font color="red">Aim</font></b><br> To develop and validate a <b>Vaccine Trust Framework</b> and a <b>trust measurement tool</b> that can be used to <i>leverage trust</i> to drive <i>resilient vaccine demand</i>. </div>

<br>

<div> <b><font color="red">Methods</font></b><br> An <i>exploratory sequential mixed-methods</i> study was conducted. <ul> <li> <b>Ethnographic research</b> in <b>Nigeria, Kenya, and Pakistan</b> to define trust in the context of <i>childhood</i>, <i>HPV</i>, and <i>COVID-19</i> vaccines. </li> <li> Validation through a <b>nationally representative survey</b> of <i>caregivers of adolescents</i> in <b>Kenya and Pakistan</b>. </li> <li> Psychometric assessment using <i>confirmatory factor analysis</i> and <i>logistic regression</i>. </li> </ul> </div>

<br>

<div> <b><font color="red">Findings</font></b> <ul> <li> The <b>Vaccine Trust Framework</b> consists of <b>four interlinked domains</b> and <b>15 measurable dimensions</b>: <br> <i>Health system promise</i>, <i>health system delivery</i>, <i>vaccine promise</i>, and <i>vaccine delivery</i>. </li> <li> Survey data were collected from <b>3670 participants in Kenya</b> and <b>3734 participants in Pakistan</b>. </li> <li> <b>Trust influenced vaccine behaviour and intentions</b>, supported by associations between <i>quantitative trust scores</i> and <i>vaccination status</i>. </li> <li> <b>Regional variation in trust</b> was observed within Kenya and Pakistan, aligning with <i>qualitative perceptions</i> of local vaccine and health systems. </li> </ul> </div>

<br>

<div> <b><font color="red">Interpretation</font></b><br> The Vaccine Trust Framework provides a <b>validated</b> and <b>contextually grounded</b> tool for assessing trust in health systems and vaccines in low-income and middle-income countries. <br><br> It can be used as a: <ul> <li><b>Prognostic tool</b> to anticipate vaccine demand</li> <li><b>Intervention design aid</b> to support <i>trust-building strategies</i></li> <li><b>Trust measurement tool</b> within <i>intervention</i> or <i>monitoring</i> studies</li> </ul> <i>Further research is ongoing</i> to assess its utility in designing and measuring the impact of <b>trust-building interventions</b>. </div>