TABLE 1.

Methods for measurement of calcium absorption or retention¹

Method	Advantages	Disadvantages
Mass balance	No tracers needed	Prolonged fecal collections needed
Single oral tracer	No IV tracer needed	Fecal collection needed, may be less accurate
Bone mineral change	No tracers or collections needed	More suitable for children, long-time period of observation needed
Dual tracer	Accurate, rapid, no stools	IV infusion needed

¹IV, intravenous.