Testing Knowledge
Test Directory
Source-backed test guides: what each test is for, how it is performed, its limitations, and which reviewed products serve it. Personal health questions are answered with knowledge and preparation guidance — not supplier sales.

Plasminogen Activator Inhibitor-1 Measurement
The determination of the amount of plasminogen activator inhibitor-1 present in a sample.
Phosphorylated Tau Protein 181 Measurement
The determination of the amount of Tau protein where threonine 181 is phosphorylated in a sample.
Gut-Homing Natural Killer T-Lymphocyte to Natural Killer T-Lymphocyte Ratio Measurement
The determination of the ratio of gut-homing natural killer T-lymphocytes to natural killer T-lymphocytes present in a sample. The measurement may be expressed as a ratio or percentage.
CD11A Expressing Cell Count
The determination of the amount of the CD11a expressing cells in a sample.
Leucine Rich Alpha-2-Glycoprotein 1 Measurement
The determination of the amount of leucine rich alpha-2-glycoprotein 1 present in a sample.
Cytochrome P450 2C9 Activity Measurement
The determination of the amount of the biological activity of cytochrome P450 2C9 in a sample.
Megakaryocyte to Total Cell Ratio Measurement
The determination of the ratio of megakaryocytes compared to total cells present in a sample. The measurement may be expressed as a ratio or percentage.
Fencamfamin Measurement
The determination of the amount of the fencamfamin in a sample.
Conventional Naive T-Lymphocyte Subpopulation Count
The determination of the number of sub-population of conventional naive T-lymphocytes in a sample.
Non-Classical Monocyte to Leukocyte Ratio Measurement
The determination of the ratio of monocytes non-classical to leukocytes present in a sample. The measurement may be expressed as a ratio or percentage.
Tapentadol Measurement
The determination of the amount of the tapentadol in a sample.
Benzo[k]fluoranthene Measurement
The determination of the amount of benzo[k]fluoranthene in a sample.
Vinyl Chloride Measurement
The determination of the amount of vinyl chloride in a sample.
CD278 Expression Measurement
The determination of the amount of cellular CD278 expression in a biological sample.
MSD V-PLEX SARS-CoV-2 Panel 2 Kit RBD IgG Serology Assay
A proprietary serology assay that can be used to measure IgG antibodies against the SARS-CoV-2 S1 spike receptor-binding domain (RBD).
Urease Measurement
The determination of the urease present in a sample.
Double-Negative B-Lymphocyte Count
The determination of the amount of double negative B-lymphocytes present in a sample.
Collagen III Neo-Peptide C3M Measurement
The determination of the amount of collagen III neo-peptide C3M present in a sample.
Serum Magnesium Measurement
A quantitative measurement of the amount of magnesium present in a sample of serum.
Soluble Vascular Endothelial Growth Factor Receptor Type 1 Measurement
The determination of the amount of soluble vascular endothelial growth factor receptor 1 present in a sample.
Hydromorphone Measurement
The determination of the amount of hydromorphone present in a sample.
Type 1 Innate Lymphoid Cell Subpopulation to Leukocyte Ratio Measurement
The determination of the ratio of a sub-population of type 1 innate lymphoid cells to total leukocytes present in a sample. The measurement may be expressed as a ratio or percentage.
Noroxycodone Measurement
The determination of the amount of noroxycodone in a sample.
Terminal Memory Cytotoxic T-Lymphocyte to Cytotoxic T-Lymphocyte Ratio Measurement
The determination of the ratio of the terminal memory cytotoxic T-lymphocytes to total cytotoxic T-lymphocytes present in a sample. The measurement may be expressed as a ratio or percentage.
