This variable is only available in MAP and MARS.
Tumor necrosis factor-α (TNF-α) level is quantified from serum samples using highly sensitive multiplexed sandwich enzyme-linked immunosorbent assay (ELISA) arrays by Endogen Searchlight technologies (Billerica, MA). See the inflammatory markers subcategory description for more information.
The lower detection limit for TNF-α is 2.3 pg/mL. In preliminary analysis, its intra-assay coefficient of variation was 3.1-5.0%, and its inter-assay coefficient of variation was 4.4-4.7%.
This variable is expressed in pg/mL and is log transformed.