Download, Parse, and Analyze NHANES Data with Mortality Linkage // Provides tools for downloading and organizing National Health and Nutrition Examination Survey (NHANES) public-use data files and the National Center for Health Statistics (NCHS) Public-Use Linked Mortality Files (LMF). Supports structured local caching, codebook access, survey-aware merging, and preparation of survival analysis datasets using NHANES-National Death Index (NDI) linked mortality data (follow-up through December 31, 2019). NHANES methodology is described at https://wwwn.cdc.gov/nchs/nhanes/Default.aspx.