Corrected calcium is an estimated calcium value adjusted for abnormal albumin levels, since total serum calcium is affected by albumin concentration.

Low albumin can make total calcium appear falsely low. Correcting calcium helps estimate the physiologically relevant level more accurately.

A common formula is: Corrected Calcium = Total Calcium + 0.8 × (4 - Albumin), using calcium in mg/dL and albumin in g/dL.

No. Ionized calcium is the most accurate reflection of active calcium status. Corrected calcium is only an estimate and should be interpreted with clinical context.