In 1994 the WHO proposed guidelines for the diagnosis of osteoporosis based
on measurement of bone mineral density. They have been widely used for epi
demiological studies, clinical research and for treatment strategies. Despi
te the widespread acceptance of the diagnostic criteria, several problems r
emain with their use. Uncertainties concern the optimal site for assessment
, thresholds for men and diagnostic inaccuracies at different sites. In add
ition, the development of many new technologies to assess the amount or qua
lity of bone poses problems in placing these new tools within a diagnostic
and assessment setting. This review considers the recent literature that ha
s highlighted the strengths and weaknesses of diagnostic thresholds and the
ir use in the assessment of fracture risk, and makes recommendations for ac
tions to resolve these difficulties.