A large national Thai Cohort Study of the Health-Risk Transition based on Sukhothai Thammathirat Open University students.

Thailand 's dynamic economic development has been accompanied by great changes in cultural, social, environmental and other forces that shape population health in ways that are poorly understood. To study Thailand's health-risk transition we began to follow a large cohort of students enrolled at Sukhothai Thammathirat Open University (STOU) - an accessible transitional group. STOU students are not affluent but are aspiring to modernize. Our Thai Cohort Study (TCS) started at baseline with 87,134 cohort members in 2005, with over 60,000 successfully being followed up in 2009; the next round of follow-up is scheduled for 2013. Here we show that the Thai population, the STOU student body and the TCS cohort are comparable for social geography and socio-economic status. Productive results make us sure the project can have substantial long-term impacts on regional population health by enabling Thailand and similar middle-income countries to understand and mitigate emerging disease trends. Our study shows that Open University students are able and willing to represent their source populations for a variety of useful social and health research.