became available. Our total sample comprises of 57 rounds of data across 36 countries amounting to over 94,000 individual-level data points (Table A1). Our experimental results focus on five of these 36 countries that are located in Sub-Saharan Africa.

The second source of data we draw on is a short survey on COVID-19 vaccination collected inperson as part of the Ethiopia Socioeconomic Survey (ESS 5), a nationally representative household survey that was implemented between April and June 2022 by the Ethiopia Statistical Service with support from the World Bank’s LSMS program. This survey contained a similar module as the phone surveys and collected information on the vaccination status of all household members.

The source of administrative data for our study is the Our World in Data (OWID) COVID-19 vaccination dataset (Mathieu et al. 2021) that compiles administrative data on COVID-19 vaccine coverage. Amongst others, the dataset contains information on the number of total doses administered, the share of the country population that has received at least one dose, and the share of the population that is fully vaccinated.<sup>3</sup> It covers the period from December 2020 when the first COVID-19 vaccines achieved approval and is regularly updated as new data becomes available on a per-country basis. The data is compiled from country reports (such as government websites, dashboards, or the social media accounts of national authorities) and in some cases third-party aggregators (where national authorities do not publish data in a machine-readable format) and is regularly audited for inconsistencies and technical errors. The Our World in Data COVID-19 vaccination dataset has been extensively used during the pandemic, for example to supply the data for the WHO’s official COVID-19 dashboard, by global media outlets, and for social science and epidemiological research (Mathieu et al. 2021). The dataset is publicly available through the Our World in Data GitHub repository.<sup>4</sup> We additionally access a second source of administrative data stemming from the WHO’s COVID19 vaccination dashboard (WHO 2020b). The dashboard does not provide longitudinal information for public access but reports the latest available COVID-19 vaccine coverage figures at the time of data access (April 2, 2023, in our case).

Lastly, we use data from the World Bank’s Statistical Performance Indicators (SPI) available through the World Bank’s Open Data library (World Bank n.d.). The SPI is a composite index between 0 – 100 scoring countries’ statistical systems across the five pillars of data use, data services, data products, data sources, and data infrastructure (Dang et al. 2023). To capture the performance of administrative data systems in particular, we also use the SPI’s indicator of administrative data capacity (Dimension 4.2) that records the availability of Civil Registration and Vital Statistics (CRVS).

> 3 Defined as the share of the total population that has completed the initial vaccine protocol: two doses or more of a two-dose vaccine (such as Comirnaty by BioNTech and Pfizer) or one shot of a single-shot vaccine (such as Janssen by Johnson & Johnson).

> 4 https://github.com/owid/covid-19-data/tree/master/public/data/vaccinations

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