Osteoporosis International

, Volume 16, Issue 12, pp 1742–1748 | Cite as

Reproducibility of bone mineral density measurements using dual X-ray absorptiometry in daily clinical practice

  • A. El Maghraoui
  • A. A. Do Santos Zounon
  • I. Jroundi
  • A. Nouijai
  • M. Ghazi
  • L. Achemlal
  • A. Bezza
  • M. A. Tazi
  • R. Abouqual
Original Article


Bone mineral density (BMD) measurements are frequently performed repeatedly for each patient. Subsequent BMD measurements allow reproducibility to be assessed. Previous studies have suggested that reproducibility may be influenced by age and clinical status. The purpose of the study was to examine the reproducibility of BMD by dual energy X-ray absorptiometry (DXA) and to investigate the practical value of different measures of reproducibility in three distinct groups of subjects: healthy young volunteers, postmenopausal women and patients with chronic rheumatic diseases. Two hundred twenty-two subjects underwent two subsequent BMD measurements of the spine and hip. There were 60 young healthy subjects, 102 postmenopausal women and 60 patients with chronic rheumatic diseases (33 rheumatoid arthritis, 10 ankylosing spondylitis and 10 other systemic diseases). Forty-five patients (75%) among the third group were receiving corticosteroids. Reproducibility was expressed as the smallest detectable difference (SDD), coefficient of variation (CV), least significant change (LSC) and intraclass correlation coefficient (ICC). Sources of variation were investigated by linear regression analysis. The median interval between measurements was 0 days (range 0–7). The mean difference (SD) between the measurements (g/cm2) was −0.0001 (±0.003) and −0.0004 (±0.002) at L1-L4 and the total hip, respectively. At L1-L4 and the total hip, SDD (g/cm2) was ±0.04 and ±0.02, CV (%) was 2.02 and 1.29, and LSC (%) 5.60 and 3.56, respectively. The ICC at the spine and hip was 0.99 and 0.99, respectively. Only a minimal difference existed between the groups. Reproducibility in the three groups studied was good. In a repeated DXA scan, a BMD change, the least significant change (LSC) or the SDD should be regarded as significant. Use of the SDD is preferable to use of the CV and LSC because of its independence from BMD and its expression in absolute units. Expressed as SDD, a BMD change of at least ±0.04 g/cm2 at L1-L4 and ±0.02 g/cm2 at the total hip should be considered significant. This reproducibility seems independent from age and clinical status and improved in the hips by measuring the dual femur.


Chronic rheumatic diseases Dual energy X-ray absorptiometry (DXA) Healthy volunteers Osteoporosis Post-menopausal women Reproducibility 


  1. 1.
    El Maghraoui A, Koumba BA, Jroundi I, Achemlal L, Bezza A, Tazi MA (2005) Epidemiology of hip fractures in 2002 in Rabat, Morocco. Osteoporos Int 16:597–602. DOI 10.1007/s00198–004–1729–8CrossRefGoogle Scholar
  2. 2.
    Bono CM, Einhorn TA (2003) Overview of osteoporosis: pathophysiology and determinants of bone strength. Eur Spine J 12 [Suppl 2]:S90–S96Google Scholar
  3. 3.
    Kanis JA, Johnell O, Oden A, Jonsson B, De Laet C, Dawson A (2000) Risk of hip fracture according to the World Health Organization criteria for osteopenia and osteoporosis. Bone 27:585–590PubMedGoogle Scholar
  4. 4.
    Yeap SS, Hosking DJ (2002) Management of corticosteroid-induced osteoporosis. Rheumatology 41:1088–1094PubMedGoogle Scholar
  5. 5.
    Maricic M, Gluck O (2004) Densitometry in glucocorticoid-induced osteoporosis. J Clin Densitom 7:359–363PubMedGoogle Scholar
  6. 6.
    El Maghraoui A (2004) Corticosteroid induced osteoporosis. Press Med 33:1213–1217Google Scholar
  7. 7.
    Phillipov G, Seaborn CJ, Phillips PJ (2001) Reproducibility of DXA: potential impact on serial measurements and misclassification of osteoporosis. Osteoporos Int 12:49–54PubMedGoogle Scholar
  8. 8.
    Nguyen TV, Sambrook PN, Eisman JA (1997) Sources of variability in bone mineral density measurements: implications for study design and analysis of bone loss. J Bone Miner Res 12:124–135PubMedGoogle Scholar
  9. 9.
    Lodder MC, Lems WF, Ader HJ, Marthinsen AE, van Coeverden SCCM, Lips P et al (2004) Reproducibility of bone mineral density measurement in daily practice. Ann Rheum Dis 63:285–289PubMedGoogle Scholar
  10. 10.
    Maggio D, McCloskey EV, Camilli L, Cenci S, Cherubini A, Kanis JA et al (1998) Short-term reproducibility of proximal femur bone mineral density in the elderly. Calcif Tissue Int 63:296–299PubMedGoogle Scholar
  11. 11.
    Ravaud P, Reny JL, Giraudeau B, Porcher R, Dougados M, Roux C (1999) Individual smallest detectable difference in bone mineral density measurements. J Bone Miner Res 14:1449–1456PubMedGoogle Scholar
  12. 12.
    Fuleihan GE, Testa MA, Angell JE, Porrino N, Leboff MS (1995) Reproducibility of DXA absorptiometry: a model for bone loss estimates. J Bone Miner Res 10:1004–1014PubMedGoogle Scholar
  13. 13.
    Rozenberg S, Vandromme J, Neve J, Aguilera A, Muregancuro A, Peretz A et al (1995) Precision and accuracy of in vivo bone mineral measurement in rats using dual-energy X-ray absorptiometry. Osteoporos Int 5:47–53PubMedGoogle Scholar
  14. 14.
    Nguyen TV, Eisman JA (2000) Assessment of significant change in BMD: a new approach. J Bone Miner Res 15:369–372PubMedGoogle Scholar
  15. 15.
    Bland J, Altman D (1986) Statistical methods for assessing agreement between methods of clinical measurement. Lancet i:307–310Google Scholar
  16. 16.
    Gluer CC (1999) Monitoring skeletal changes by radiological techniques. J Bone Miner Res 14:1952–1962PubMedGoogle Scholar
  17. 17.
    Johnson SL, Petkov VI, Williams MI, Via PS, Adler RA (2004) Improving osteoporosis management in patients with fractures. Osteoporos IntGoogle Scholar
  18. 18.
    Prevention and management of osteoporosis. World Health Organ Tech Rep Ser 2003; 921:1–164Google Scholar
  19. 19.
    Kanis JA, Devogelaer JP, Gennari C (1996) Practical guide for the use of bone mineral measurements in the assessment of treatment of osteoporosis: a position paper of the European foundation for osteoporosis and bone disease. The Scientific Advisory Board and the Board of National Societies. Osteoporos Int 6:256–261PubMedGoogle Scholar
  20. 20.
    El Maghraoui A, Borderie D, Edouard R, Roux C, Dougados M (1999) Osteoporosis, body composition and bone turnover in ankylosing spondylitis. J Rheumatol 26:2205–2209PubMedGoogle Scholar
  21. 21.
    El Maghraoui A (2004) Osteoporosis and ankylosing spondyltis. Joint Bone Spine 71:573–578Google Scholar
  22. 22.
    Eastell R (1996) Assessment of bone density and bone loss. Osteoporos Int [Suppl] 6:3–5Google Scholar

Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2005

Authors and Affiliations

  • A. El Maghraoui
    • 1
  • A. A. Do Santos Zounon
    • 1
  • I. Jroundi
    • 2
  • A. Nouijai
    • 1
  • M. Ghazi
    • 1
  • L. Achemlal
    • 1
  • A. Bezza
    • 1
  • M. A. Tazi
    • 3
  • R. Abouqual
    • 2
  1. 1.Rheumatology and Physical Rehabilitation DepartmentMilitary Hospital Mohammed VRabatMorocco
  2. 2.Epidemiology and Biostatistics DepartmentFaculty of Medicine and PharmacyRabatMorocco
  3. 3.Epidemiology DepartmentMinistry of HealthRabatMorocco

Personalised recommendations