Vitamini D ndi vitamini komanso ndi mahomoni a steroid, makamaka VD2 ndi VD3, omwe malangizo awo ndi ofanana kwambiri.Vitamini D3 ndi D2 amasinthidwa kukhala 25 hydroxyl vitamini D (kuphatikiza 25-dihydroxyl vitamini D3 ndi D2).25-(OH) VD m'thupi la munthu, malangizo okhazikika, okwera kwambiri.25-(OH) VD imasonyeza kuchuluka kwa vitamini D, ndi mphamvu ya kutembenuka kwa vitamini D, kotero 25-(OH) VD imatengedwa kuti ndi chizindikiro chabwino kwambiri chowunika mlingo wa vitamini D. The Diagnostic Kit imachokera immunochromatography ndipo amatha kupereka zotsatira mkati mwa mphindi 15.