A possible measure for evaluating health system performance is the achievement index, which can be calculated using prevalence and distribution of a health measure across different socioeconomic groups. This study extends this approach by examining how achievement can be represented on a...

During the COVID-19 pandemic, governments offered financial incentives to increase vaccine uptake. We evaluate the impact on COVID-19 vaccine uptake of cash equivalents versus being entered into lotteries. We randomly assign 1628 unvaccinated US participants into one of three 45-second...