Bone alkaline phosphatase (ALP) is a marker of bone formation and metabolism.
Bone ALP was measured by electrophoresis & chemiluminescent enzyme immunoassay.
When ALP3 isozyme predominated, the two methods showed good correlation.
From ALP3 (%) < 23, correlation between the two methods deteriorated.
In some special cases, the accuracy of the electrophoresis is questionable.