لخّصلي

Survey design
The survey was carried out by the SAGE secretariat which, in addition to its role of leading all SAGE related activities, also has a wider coordination function concerning all matters of relevance to immunization policy at global, regional and country level. Each NITAG for whom WHO could access contact details was invited to select a single representative to complete a voluntary 4-part sur- vey consisting of 29 questions. An initial section collected basic information about the NITAG and the country context. A second section was dedicated to accessibility, suitability and usability of COVID-19 vaccine policy outputs published by WHO. The third sec- tion aimed to collect insights on the role and process each NITAG has played or followed to develop COVID-19 vaccine policies. Lastly, there was a brief fourth section focusing on COVID-19 policy challenges that was intended to help rapidly identify stress points around issues of concern in vaccine policy development, as well as where vaccine policy gaps persist. The survey was available in Eng- lish, French, Spanish and Russian (Annex 1).
In order to verify the survey was fit for purpose and to ensure all questions could be adequately interpreted and answered by NITAGs from broad-ranging geographic and economic settings, as well as levels of committee maturity, a brief piloting and validation of the survey was implemented, including the translated versions in Spanish and French. The survey was piloted among the six mem- bers of the GNN steering committee, representing each of the WHO regions3. The survey was assessed not to require full WHO ethics review by the WHO Research Ethics Review Committee as no per- sonal patient data was collected given the system quality improve- ment objectives of the survey (ref.CERC.0144).
2.2. Data collection
A link to an online survey, created for maximum simplicity and efficiency through Microsoft Forms, was sent out in late November 2021 to a total of 98 NITAGs by email to both the secretariat lead and the chair of each advisory group, requesting a coordinated response and offering the option to complete a version in one of the four languages. The 98 NITAGs contacted included the sub- regional Immunization Technical Advisory Group for the Caribbean region (CITAG) that encompasses 22 countries and territories/13 WHO Member States [9], and the 74 registered GNN members, as well as additional NITAGs for whom contact information was avail- able as a result of registration for SAGE meetings or communica- tions with WHO regional office focal points. Regional office focal points were also encouraged to disseminate the survey to addi- tional countries and to follow up with country offices to increase the response rate. NITAGs were given three weeks to respond to the survey which was estimated to require approximately 20 min to complete. Multiple reminders were sent out as the sur- vey deadline approached. Only one response per NITAG was accepted as well as the collective response from the CITAG on behalf of Caribbean countries- operating as a single NITAG for the purposes of the survey. Additional data on regional categories, World Bank income-level, and NITAG functionality status (accord- ing to WHO criteria) were added to the dataset to allow for addi- tional stratifications and comparisons, but these were not factors in the sample selection. Countries without a NITAG were not
3 https://www.nitag-resource.org/network/steering-committee
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approached as they were determined to be beyond the scope of this survey.
2.3. Analysis
Full text responses in languages other than English were trans- lated into English.
Descriptive statistical analysis was conducted using Microsoft Excel, and grouped thematically by survey section, as well as through regional and economic stratification. Qualitative findings were subjected to simple thematic analysis, based on the survey structure, with similar themes grouped together.
Given the small sample size and the self-selection permitted within the sampling methodology, inferential analysis was deemed inappropriate. While stratification of survey responses was sys- tematically conducted per income classification and WHO region, only the most relevant results are commented on.
The results of the survey were presented to the SAGE Working Group for COVID-19 and to SAGE members, who expressed their satisfaction with the findings.