Health levels varied greatly among people 50 and older in China, Ghana, India, Mexico, Russia and South Africa, but hypertension and arthritis were the two most common chronic conditions in all six countries according to the first-ever U.S. Census Bureau report to use data from the Study on Global Ageing and Adult Health (SAGE). Commissioned by the National Institute on Aging (NIA) of the National Institutes of Health, the report, Shades of Gray: A Cross-Country Study of Health and Well-Being of the Older Populations in SAGE Countries, 2007-2010, examines the health status and access to health care among older populations in the aforementioned six low- to middle-income countries, which are each among the world's 50 most populous.