Protocol for the development and psychometric validation of the COM-B readiness to promote vaccination questionnaire for healthcare professionals in four European countries

Introduction Annual seasonal vaccinations for influenza and COVID-19 are considered to have high public health and economic benefits. Healthcare professionals (HCPs) have a crucial role in individuals’ vaccination decision. However, encouraging HCPs to actively promote vaccination remains challenging. The Capabilities, Opportunities, Motivation-Behaviour (COM-B) model of behaviour offers a framework for identifying individual and contextual factors influencing HCPs’ readiness to promote vaccination. To our knowledge, there are currently no quantitative tools measuring HCPs’ readiness to promote vaccination based on the COM-B Model. Objectives To develop a questionnaire informed by the COM-B model on the readiness of HCPs to promote COVID-19 and influenza vaccination, to assess the cross-national adaptation of the questionnaire across the co-OPERATOR consortium countries (Cyprus, Greece, Italy, Portugal), and to evaluate the validity, reliability, and acceptability of the different language versions. Protocol The questionnaire will be developed in three phases: Item development, questionnaire development, and questionnaire evaluation. Items were developed using deductive methods applied through literature review and assessment of existing scales and items tapping on COM-B domains. Content validity was tested using an Expert Consensus Study. Forward-backward translations will be employed to translate the tool from English into the target languages, and local experts will provide feedback on the suitability of the translated equivalent versions. Cognitive interviews with end-users will take place to assess the understandability and usability of the questionnaire, and appropriateness of response options. The questionnaire will subsequently be distributed to HCPs in the different countries to evaluate its metric properties (e.g., construct validity, reliability) and users’ acceptability. A sub-sample of participants will complete the questionnaire twice, with a 2-week interval. Conclusion A valid and reliable theory-based questionnaire can be used in various clinical settings in different countries to provide measurable, comparable outcomes and performance metrics to support policymaking decisions and vaccination promotion strategies.