: Refers to a specific group of survey participants, specifically those part of the 2015 HOS Baseline.
If you were looking for an archive tool, you might be thinking of the , which is a popular app for opening ZIP and RAR files. B18zip
"B18zip" is a specific data field label used in medical health research datasets, most notably in the documentation . : Refers to a specific group of survey
: The name typically stands for "Cohort 18 Baseline ZIP Code" . you might be thinking of the