Cohort profile: the PROLIFE study in Kerala, India.

Population Registry of Lifestyle Diseases (PROLIFE) is a prospective cohort study aimed at the long-term follow-up of the residents of seven contiguous villages in Kerala, India. There were 161 942 subject enrolments as of 1 July 2002. The study was initiated by Health Action by People (HAP), a non-profit public health research organization. Kerala, with a population of 431 million in 2001, has the best health indicators in India. The ‘Kerala health experience’ has been much discussed in academic circles. The dramatic declines in fertility and mortality in the state have resulted in a rapid epidemiological transition characterized by high morbidity and mortality from chronic diseases. However, valid epidemiological information on the burden of chronic diseases in the population does not exist. We have to rely on secondary data from hospitals. HAP decided to bridge the data gap by setting up PROLIFE.