One autumn day in 1981 a crew of a foreign ship, who was in a hospital of Chongjin City, North Hamgyong Province in the DPRK, asked his doctor where doctors of the hospital went everyday with first-aid bags on their shoulders.
The doctor told the crew that the DPRK regards it as the main to prevent diseases before treating the people who are ill with them according to the preventive medicine policy of the Workers’ Party of Korea and explained about contents of the district doctor system.