I refer to a lengthy  message on
<sci.med.disease.osteoporosis> posted by

        Rather than reproduce the whole thing, which I hope Hon.
Members in the relevant medical field will read, I quote the passage
that concerns me.

"In older women, where discordance is less of a problem, the
likelihood of missing a diagnosis of osteoporosis when measuring only
one skeletal site such as the wrist, heel, or hip is reduced.

Emphasis added in the following:

"The exception in the elderly is a single measurement of the posterior
anterior spine by dual energy x-ray absorptiometry, where artefacts
such as osteophytes can spuriously increase the value of one mineral
density measurements."

It  sounds like they are saying it can give a false measurement of the
amount of bone loss.  But which way?  Under-state, or over-state?

TIA

--
Polar