I never use a single diagnostic tool but rather use diagnostics + symptoms + case history to lead me to the organs of greatest involvement. All I need is a starting point because when the root is treated the body does the rest (the body is miraculous).
This is very different than only treating the number (lab number = drug (or lab number = supplement for those dr's promoting "functional medicine")). Treating the number will result in a bag full of supplements without any understanding of the compromised physiology.