With regards to socioeconomic status, the China–Cornell–Oxford Project, a 20-year study—described by The New York Times as "the Grand Prix of epidemiology"—conducted by the Chinese Academy of Preventive Medicine, Cornell University, and the University of Oxford where T. Colin Campbell was one of the study's directors.[8] It looked at mortality rates from cancer and other chronic diseases from 1973–75 in 65 counties in China; the data was correlated with 1983–84 dietary surveys and blood work from 100 people in each county. The research was conducted in those countries because they had genetically similar populations that tended, over generations, to live and eat in the same way in the same place. The study concluded that counties with a high consumption of animal-based foods in 1983–84 were more likely to have had higher death rates from "Western" diseases as of 1973–75, while the opposite was true for counties that ate more plant-based foods.[9]
Urban areas tended towards more meat consumption where meat was considered a luxury, and rural diets were more plant based, a high % of rural participants could not afford meat.