Significant Differences in UK and US Female Bone Density Reference Ranges

Summary In the United Kingdom (UK), T- and Z-scores are usually calculated using reference ranges derived from United States (US) populations. In the UK arm of a recent randomised trial (International Breast Cancer Intervention Study II (IBIS-II)), substantially, fewer women than expected were recruited into the osteopenic \( \left( { - {2}.{5} 45 years with a typical body mass index of 28 kg m−2 have spine and hip bone mineral density (BMD) 0.6 standard deviation higher than their US counterparts.