Figure 2.

World map illustrating the geographical dispersal of all consenting participants across studies. Regional groupings are inspired by the World Health Organization (WHO) regional classification. To reflect English language-speaking countries, the WHO region of the Americas was separated into North and South America. Similarly, Australia and New Zealand were considered separately from the Western Pacific region, as Oceania. Country-specific data indicate only two participants in Africa, and so this was combined with countries in the WHO Eastern Mediterranean region to create the Middle East and Africa region.