The MLSFH sample procedures during 1998—2012 are described in the MLSFH Cohort Profile. Below is some additional information about the initial MLSFH sample selection in 1998, and the sampling for the MLSFH adolescent cohort in 2004. In 2008 the MLSFH added a new sample of approximately 800 parents of MLSFH respondents was drawn from family listings from MLSFH respondents in 2006. All living biological parents who resided in the same village as the respondent were included in the 2008 MLSFH new sample of parents. Also, as with previous waves, all previous respondents and new spouses were also included in the study.