**2. Materials and Methods**

Strategy mapping followed a two-phased approach. Phase I (2019) led by Dadari and colleagues focused on 13 Gavi-supported countries (Afghanistan, Central African Republic, Chad Republic, Democratic Republic of Congo, Ethiopia, India, Kenya, Kyrgyzstan, Madagascar, Myanmar, Nigeria, Pakistan, Uganda) [13]. Phase II (expanded mapping in 2021) considered data from 48 additional Gavi-supported countries. A list of countries selected for both phases is available in Appendix A.
