Reference Range
Vitamin K is an essential, lipid-soluble vitamin that plays a vital role in the production of coagulation proteins.
The reference range of vitamin K is 0.2-3.2 ng/mL, but impaired blood clotting has been associated with levels below 0.5 ng/mL by one source.
Another source cites a reference range of 0.10-2.2 ng/mL.