Kyushu and Okinawa Population Study (KOPS): a large prospective cohort study in Japan.

Purpose: The Kyushu and Okinawa Population Study (KOPS) was established to investigate gene-environmental interactions in non-communicable diseases in Japan. Besides collecting blood samples and anthropometric measurements, we also obtained medical histories, psychological status and lifestyle habits, including physical activities and dietary patterns.

Participants: KOPS is a community-based prospective cohort study and consists of participants from four southwestern areas in Japan.