Webber C E
Department of Nuclear Medicine, Hamilton Health Sciences Corporation, Ont.
Clin Invest Med. 1998 Apr;21(2):88-93.
In the diagnosis and management of osteopenia and osteoporosis, dual photon absorptiometric measurements of lumbar spine and proximal femur bone mineral density are interpreted by calculating a T score, which is the number of standard deviations by which a result deviates from the mean bone density in young adults of the same sex. Threshold values are then used to categorize patients as having osteopenia or osteoporosis. The uncertainty associated with a single bone mineral density measurement, as well as the uncertainties in the assumed values for the bone mineral density in young adults and the population standard deviation, combine to create an uncertainty in the calculated T score. It is estimated that 95% of bone density measurements have a T score uncertainty of less than 0.4. This means that a single measurement of bone mineral density should not be used in isolation to assign a given patient to a specific diagnostic category. Rather, a bone mineral density measurement should be regarded as only one of the variables that determine the risk of fracture in a given patient.
在骨质减少和骨质疏松症的诊断与管理中，通过计算T值来解读腰椎和股骨近端骨矿物质密度的双光子吸收测量结果，T值是指测量结果相对于同性别年轻成年人平均骨密度的标准差数量。然后使用阈值将患者分类为患有骨质减少或骨质疏松症。单次骨矿物质密度测量的不确定性，以及年轻成年人骨矿物质密度假设值和总体标准差的不确定性，共同导致计算出的T值存在不确定性。据估计，95%的骨密度测量的T值不确定性小于0.4。这意味着不应单独使用单次骨矿物质密度测量结果来将特定患者归为特定诊断类别。相反，骨矿物质密度测量应仅被视为决定特定患者骨折风险的变量之一。
