You do not need assumptions
The NHS symptoms list groups them into general anaemia symptoms (tiredness, breathlessness, headaches, loss of appetite, weight loss) and neurological signs (peripheral neuropathy, balance problems, depression, memory and concentration changes, sometimes mood changes or psychosis in advanced cases)
In general, commenters believed this threshold would help distinguish between older, lower-cost diagnostic radiopharmaceuticals and newer, higher-cost precision diagnostic radiopharmaceuticals
This process apparently starts when the VEGF protein, which is considered to be secreted by oxygen-deprived cells during a hypoxic response, and may bind to VEGF receptors on the surface of endothelial cells