Measures of Inflammation and Immune Function: Appendix 1

<span style="font-size: 12.0pt; mso-bidi-font-size: 11.0pt; line-height: 115%;">During Wave IV, Add Health collected biological specimens from a large, nationally representative sample of young adults. Given the size of the Wave IV sample, its geographic distribution, and in- home setting of the respondent interviews, biological specimen collection involved practical, relatively non-invasive, cost-efficient and innovative methods. These methods included collection of capillary whole blood via finger prick by trained and certified field interviewers, its in situ desiccation, then shipment, assay and archival of dried blood spots. The collection of capillary whole blood followed the collection of cardiovascular and anthropometric measures (Entzel et al., 2009) and saliva (Smolen et al., 2013). It preceded the collection of data on respondent use of prescription and select over-the-counter medications (Tabor et al., 2010). Further details on the design of Add Health Waves I-IV, are available elsewhere (Harris, 2019), as are descriptions of the previously assayed biomarkers (Whitsel et al., 2012a; 2012b; 2013).</span> After Wave V (in 2019-2020), the archived dried blood spots were assayed for seven additional measures of inflammation and immune function by two Add Health ancillary studies: [1] &ldquo;Life Course Process of Alzheimer&rsquo;s Disease: Sex Difference and Biosocial Mechanisms&rdquo; (R01AG057800) (Yang and Aiello) and [2] &ldquo;Health Disparities: Inflammatory Response, Immune Function, and Environmental (In)Congruence&rdquo; (R21HD095448) (Hargrove and Gaydosh). This document summarizes the rationale, equipment, protocol, assays, internal quality control, data cleaning, and external quality control for each one of the seven measures. Whenever possible, data collection and methods in Wave V mirrored those of Wave IV to ensure comparability of data between waves, although important inter-Wave differences exist and are grey-highlighted herein.