Jiang Huang: Blood regulator or tonic for the Spleen?

Curcuma longa L. (Rhizome) jiang huang is often used clinically for its pain-relieving and anti-inflammatory qualities. It is typically added to a formula to help relieve blood stasis, particularly if there is an element of cold involved as this herb is reputed to be slightly warming. Clinically, it is often prescribed as a decoction, or in a concentrated powder/granule form. It may also be made up as a hydro-ethanolic tincture or prescribed as a crude powder - but how important is the dosage form to the effectiveness of the treatment and what can be measured in order to assess this?