%0 Journal Article %A Heidari, Behnam %A Khashayar, Patricia %A Rezai Homami, Mohsen %A Pajouhi, Atieh %A Soltani, Akbar %A Larijani, Bagher %T Dual-energy X-ray absorptiometry diagnostic discordance between Z-scores and T-scores in a young Iranian population %J Medical Journal of the Islamic Republic Of Iran %V 28 %N 1 %U http://mjiri.iums.ac.ir/article-1-2617-en.html %R %D 2014 %K Osteoporosis, Bone Mineral Density, T-scores, Z-scores, Iran., %X   Background: Dual-energy X-ray Absorptiometry (DXA) is considered the gold standard for non-invasive measurement of bone mass. T-scores and Z-scores are used to present the results of bone mass. The present study was designed to evaluate the discordance between T-scores and Z-scores calculated at a same level and its relation with age, gender and body mass index (BMI) in a representative sample of normal population.   Methods :This cross-sectional study was conducted as a part of a comprehensive survey, Iranian Multicenter Osteoporosis Study (IMOS), designed to assess bone health among healthy adults. Each individual underwent both L1–L4 antero-posterior lumbar spine and hip DXA scan. The difference between the T- and Z-scores measured at each of the four skeletal sites was then calculated.   Results : A -1.21 to 1.21 point difference was noted in the Z- and T- scores measured at each site. While the difference between the T- and Z-scores was less than 0.5 SD in most of the cases, the difference was higher than 1 SD in about 5% of the subjects.   Conclusion : Standardization of Z-score definition and calculation techniques as well as developing an ethnicity-matched reference population is needed to improve the reliability of DXA-generated Z-scores.   %> http://mjiri.iums.ac.ir/article-1-2617-en.pdf %P 1016-1022 %& 1016 %! %9 Original Research %L A-10-1-760 %+ Endocrinology & Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran. %G eng %@ 1016-1430 %[ 2014