The Chi Linh Health and Demographic Surveillance System (CHILILAB HDSS) was established in 2004 in Chi Linh District, Hai Duong Province (Northern Vietnam). Up to 2013, 22 rounds of data collection at CHILILAB HDSS had been completed. This article reports the methods and key sociodemographic characteristics of households and individuals captured by the survey conducted among the subsamples of CHILILAB HDSS in 2016. We observed and compared them to the previous HDSS survey rounds and found no significant differences for household size and gender compositions in CHILILAB HDSS. The educational level and economic status of CHILILAB people in 2016 have improved. However, it can be seen that the Chi Linh population is undergoing a strong "aging" trend.
Keywords: CHILILAB; HDSS; Vietnam; demographic surveillance.