It is compared to non-vaccinated regions, if you had bothered to read the article. > To calculate mortality in the three countries, where death registry statis

It is compared to non-vaccinated regions, if you had bothered to read the article. > To calculate mortality in the three countries, where death registry statistics are unreliable, the researchers employed tens of thousands of community reporters—more than 14,000 of them in Kenya alone—to conduct household surveys of childhood deaths in 79 areas where the RTS,S vaccine was administered and 79 comparator areas where it was not available.