The impact of bone area on short-term bone density precision

J Clin Densitom. 2006 Apr-Jun;9(2):150-3. doi: 10.1016/j.jocd.2005.12.001. Epub 2006 Apr 18.

Abstract

It has been proposed that bone area on two scans should be very close (within 2%) in order to ensure a valid comparison, but this recommendation has not been critically evaluated. We assessed the importance of bone area in test precision within a regional testing program that maintains a large quality assurance database (208 analyzable scan-pairs). Differences in bone area exceeding the "2% rule" were common (22-46% depending upon site). Scan-pairs that exceeded the 2% rule were associated with significantly greater bone density measurement error for the lumbar spine (p<0.005) and femoral neck (p=0.001), but not the total hip. A simpler "1-cm(2) rule" for the lumbar spine also predicted significantly worse spine precision (p<0.005). In conclusion, differences in bone area are sources of short-term bone density measurement error.

MeSH terms

  • Absorptiometry, Photon / standards*
  • Bone Density*
  • Female
  • Hip / physiology
  • Humans
  • Lumbar Vertebrae / physiology
  • Male
  • Middle Aged
  • Quality Assurance, Health Care