Diagnostic notes--lumbar BMC reproducibility as evaluated by means of dual photon absorptiometry.

Three evaluations of lumbar bone mineral content (BMC) were carried out at different times at intervals of a few days in 10 normal volunteers aged between 18 and 60. The dual photon absorptiometry technique was employed (using gadolinium-153 as radioactive isotope). Data on 20 subjects aged from 23 to 62 were recorded on magnetic tape and processed ten times by the same operator. The data for individual subjects proved satisfactorily reproducible and the repeated processing of a single scan by the same investigator gave very satisfactory results. The findings demonstrate that the evaluation of lumbar BMC by dual photon absorptiometry can provide highly reproducible and acceptably accurate data.