The interval between the bone density tests was 6 months. She actually lost only 3.3%. The annualized loss was 7%. It is true that a 7% loss would be statistically significant, but 5-10% of women will have a change of 3% due to imprecision of the densitometer.

The shorter the interval between measurements, the more unreliable is the annualized loss.

Updated 8/8/05