Abstract
The effect of two methods for standardizing dual-energy X-ray absorptiometry (DXA) measurements on patient classification by theT-score has been determined for a group of over 2000 patients. The methods proposed by the International DXA Standardization Committee and the European Community's COMAC-BME group were used in conjunction with young reference data from the major DXA manufacturers, the COMAC-BME group and the third US National Health and Nutrition Examination Survey (NHANES III). The two standardization techniques produced dissimilar classifications as measured by the kappa statistic (κ=0.34−0.90), especially for the femoral neck, with up to 24.3% of patients reclassified from osteopenic to normal and 18.6% reclassified from osteoporotic to osteopenic when the standardization method was changed. Considering the effects of both reference data and standardization techniques together, there was a wide variation of patient classification, with the number of patients classified as osteoporotic varying from 9.6% to 21.1% for the postero-anterior spine L2–4 region and from 2.3% to 27.6% for the femoral neck. The agreement between different classifications ranged widely, from very poor to excellent (κ=0.02–0.98). The creation of standardized reference data must be an important priority in order to harmonize patient management using standardized BMD measurements. The choice of standardization technique, however, must be addressed in light of the results presented here.
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Cullum ID, Ell PJ, Ryder JP. X-ray dual-photon absorptiometry: a new method for the measurement of bone density. Br J Radiol 1989;62:587–92.
Johnson J, Dawson-Hughes B. Precision and stability of dual-energy X-ray absorptiometry measurements. Calcif Tissue Int 1991;49:174–8.
LeBlanc AD, Schneider VS, Engelbretson DA, Evans JH. Precision of regional bone mineral measurements obtained from total-body scans. J Nucl Med 1990;31:43–5.
Kelly TL, Slovik DM, Neer RM. Calibration and standardisation of bone mineral densitometers. J Bone Miner Res 1989;4:663–9.
Laskey MA, Flaxman ME, Barker RW, Trafford S, Hayball MP, Lyttle KD, et al. Comparative performance in vitro and in vivo of Lunar DPX and Hologic QDR-1000 dual energy X-ray absorptiometers. Br J Radiol 1991;64:1023–9.
Lewis MK, Blake GM, Fogelman I. Patient dose in dual X-ray absorptiometry. Osteoporosis Int 1994:4:11–5.
Vainio P, Ahonen E, Leinonen K, Sievanen H, Koski E. Comparison of instruments for dual-energy X-ray bone mineral densitometry. Nucl Med Commun 1992;13:252–5.
Lai KC, Goodsitt MM, Murano R, Chestnut CH. A comparison of two dual-energy X-ray absorptiometry systems for spinal bone mineral measurement. Calcif Tissue Int 1993;50:203–8.
Morrita R, Orimo H, Yamamoto I, Fukunaga M, Shiraki M, Nakamurra T, et al. Some problems of dual-energy x-ray absorptiometry in the clinical use. Osteoporosis Int 1993;(Suppl 1):S87–90.
Svendsen OL, Marslew V, Hassager C, Christiansen C. Measurements of bone mineral density of the proximal femur by two commercially available dual eneregy X-ray absorptio-metric systems. Eur J Nucl Med 1992;19:41–6.
Compston JE, Cooper C, Kanis JA. Bone densitometry in clinical practise. BMJ 1995;310:1507–10.
Nord RH. Work in progress: a cross-correlation study on four DXA instruments designed to culminate in inter-manufacturer standardization. Osteoporosis Int 1992;2:210–1.
Genant HK, Grampp S, Gluer CC, Faulkner KG, Jergas M, Engelke K, et al. Universal standardisation for dual X-ray absorptiometry: patient and phantom cross-calibration results. Bone Miner Res 1994;9:1503–14.
Steiger P. Standardization of spine BMD measurement [letter]. J Bone Miner Res 1995;10:1602–3.
Dequeker J, Reeve J, Pearson J, Bright J, Felsenberg D. Multicentre European COMAC-BME study on the standardisation of bone densitometry procedures. Technol Health Care 1993;1:127–31.
Pearson J, Ruegsegger P, Dequeker J, et al. European semi-anthropomorphic phantom for the cross-calibration of peripheral bone densitometers: assessment of precision, accuracy and stability. Bone Miner 1994;27:109–20.
Pearson J, Dequeker J, Reeve J, Felsenberg D, Henley M, et al. Dual X-ray absorptiometry of the proximal femur: normal European values standardised with the European spine phantom. J Bone Miner Res 1995;10:315–24.
Pearson J, Dequeker J, Henley M, Bright J, Reeve J, et al. European semi-anthropomorphic spine phantom for the calibration of bone densitometers: assessment of precision, stability and accuracy. Osteoporosis Int 1995;5:174–84.
Kalender WA, Fesenberg D, Genant HK, Fischer M, Dequeker J, Reeve J. The European spine phantom: a tool for standardization and quality control in spinal bone mineral measurements by DXA and QCT. Eur J Radiol 1995;20:83–92.
Kalender WA. A phantom for standardization and quality control in spinal bone mineral measurements by QCT and DXA: design considerations and specifications. Med Phys 1992;19:583–6.
Kanis JA, Melton LJ, Christiansen C, Johnston CC, Khaltev N. The diagnosis of osteoporosis. J Bone Miner Res 1994;9:1137–41.
Eastell R, Peel NFA. Interpretation of bone density results. Osteoporos Rev 1994;2:1–3.
Laskey MA, Crisp AJ, Cole TJ, Compston JE. Comparison of the effect of different reference data in Lunar DPX and Hologic QDR-1000 dual-energy X-ray absorptiometers. Br J Radiol 1992;65:1124–9.
Pocock NA, Sambrook PN, Nguyen T, et al. Assessment of spinal and femoral bone density by dual X-ray absorptiometry: comparison of Lunar and Hologic instruments. J Bone Miner Res 1991;7:1081–4,
Simmons A, Barrington S, O'Doherty MJ, Coakley AJ. DEXA normal reference range use within the UK and the effect of different normal ranges on the assessment of bone density. Br J Radiol 1995;68:903–9.
Simmons A, O'Doherty MJ, Barrington S, Coakley AJ. A survey of dual-energy x-ray absorptiometry normal reference ranges used within the United Kingdom and their effect on patient classification. Nucl Med Comm 1995;16:1041–53.
Dequeker J, Pearson J, Reeve J, Henley M, Bright J, Felsenberg D, et al. Dual X-ray absorptiometry: cross-calibration and normative reference ranges for the spine. Results of a European Community concerted action. Bone 1995;17:247–54.
Looker AC, Wahner HW, Dunn WL, Calvo MS, Harris TR, Heyse SP, et al. Proximal femur bone mineral levels of US adults. Osteoporosis Int 1995;5:389–409.
Lai KC, Goodsitt MM, Murano R, Chesnut CH III. A comparison of two dual-energy x-ray absorptiometry systems of spinal bone mineral measurement. Calcif Tissue Int 1992;50:203–8.
Reid DM, Lanham SA, McDonald AG, Averell A, Fenner JAH, Boyle IT, Nuki G. Speed and comparability of three dual-energy x-ray absorptiometer (DXA) models. In: Overgaard K, Christiansen C (eds) Osteoporosis 1990, vol 2. Copenhagen: Osteopress, 1990:575–7.
Pocock W, Sambrooke P, Nguyen T, Kelly P, Freund J, Eisman J. Assessment of spinal and femoral bone density by dual x-ray absorptiometry: comparison of Lunar and Hologic instruments. J Bone Miner Res 1992;7:1081–4.
Arai H, Nagao K, Furutuchi K. The evaluation of three different bone densitometry systems: XR-26, QDR-1000 and DPX. Image Technol Inform Display 1990;22:1–6.
Gundry GR, Miller CW, Ramos E, Moscona A, Stein JA, Mazess RB, et al. Dual-energy radiographic absorptiometry of the lumbar spine: clinical experience with two different systems. Radiology 1990;174:539–4.
Vainio P, Ahonen E, Leinonen K, Sievanen H, Koski E. Comparison of instruments for dual-energy x-ray bone mineral densitometry. Nucl Med Commun 1992;13:252–5.
Laskey MA, Flaxman ME, Barger RW, et al. Comparative performance in vivo and in vitro of Lunar DPX and Hologic QDR-1000 dual energy x-ray absorptiometers. Br J Radiol 1991;64:1023–9.
Tothill P, Fenner JAK, Reid DM. Comparisons between three dual-energy x-ray absorptiometers used for measuring spine and femur. Br J Radiol 1995;68:621–9.
Tothill P. Cross-calibration of DXA scanners for spine measurements. Osteoporosis Int 1995;5:410–11.
Nord RH. Performance of the European spine phantom: an evaluation from published data. Osteoporosis Int 1996;6:99.
Mazess RB, Barden HS, Ettinger M, et al. Spine and femur density using dual-photon absorptiometry in US white women. Bone Miner 1987;2:211–9.
Garn S, Rohmann CG, Wagner B. Bone loss as a general phenomenon in man. Fed Proc 1967;26:1729–36.
Goldsmith NF, Johnston JO, Picetti G, et al. Bone mineral in the radius and vertebral osteoporosis in an insured population. J Bone Joint Surg Am 1973;55:1276–93.
Riggs BL, Wahner HW, Melton LJ III, et al. Rates of bone loss in the appendicular and axial skeletons of women: evidence of substantial vertebral bone loss before menopause. J Clin Invest 1986;77:1487–91.
Geusens P, Dequeker J, Verstraeten A, et al. Age-, sex-, and menopause-related changes of vertebral and peripheral bone: population study using dual and single photon absorptiometry and radiogrammetry. J Nucl Med 1986;27:1540–9.
Bonjour JP, Theintz G, Law F, Slosman D, Rizzoli R. Peak bone mass. Osteoporosis Int 1994;4:7–13.
Recker RR, Davies KM, Hinders SM, et al. Bone gain in young adult women. JAMA 1992;268:2403–8.
Matkovic V, Jelic T, Wardlaw GM, et al. Timing of peak bone mass in Caucasian females and its implication for the prevention of osteoporosis. J Clin Invest 1994;93:799–808.
Sabatier JP, Guaydiersouquieres G, Laroche P, et al. Bone mineral acquisition during adolescence and early adulthood: a study in 574 healthy females 10–24 years of age. Osteoporosis Int 1996;6:141–8.
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Simmons, A., Simpson, D.E., O'Doherty, M.J. et al. The effects of standardization and reference values on patient classification for spine and femur dual-energy X-ray absorptiometry. Osteoporosis Int 7, 200–206 (1997). https://doi.org/10.1007/BF01622289
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DOI: https://doi.org/10.1007/BF01622289