The NLSY Kinship Links: Using the NLSY79 and NLSY-Children Data to Conduct Genetically-Informed and Family-Oriented Research

Abstract

The National Longitudinal Survey of Youth datasets (NLSY79; NLSY-Children/Young Adults; NLSY97) have extensive family pedigree information contained within them. These data sources are based on probability sampling, a longitudinal design, and a cross-generational and within-family data structure, with hundreds of phenotypes relevant to behavior genetic (BG) researchers, as well as to other developmental and family researchers. These datasets provide a unique and powerful source of information for BG researchers. But much of the information required for biometrical modeling has been hidden, and has required substantial programming effort to uncover-until recently. Our research team has spent over 20 years developing kinship links to genetically inform biometrical modeling. In the most recent release of kinship links from two of the NLSY datasets, the direct kinship indicators included in the 2006 surveys allowed successful and unambiguous linking of over 94 % of the potential pairs. In this paper, we provide details for research teams interested in using the NLSY data portfolio to conduct BG (and other family-oriented) research.

Keywords: Behavior genetics; Biometrical modeling; Cousins; Kinship links; NLSY79; NLSY97; NLSYC; Siblings.

Fig. 1

Time relationship among the three NLSY dataset birth periods, survey dates, and childbearing periods; arrows indicated that the process is still ongoing; the green vertical line indicates year in which explicit kinship indicators were collected in NLSY79 and NLSYC. (DOB stands for “Date of Birth”)

Fig. 2

Using ROC curve logic, the performance of each algorithm version was monitored to inform future versions. The tension between the implicit and explicit assignments among Gen2 pairs eventually arrived at a 21:1 agreement-to-disagreement ratio. The axes represent the counts of agreement/disagreement, and the text indicates the algorithm version (which progresses from version 1 to version 40). The right panel zooms on the relevant movement