Decision rules for selecting women for bone mineral density testing: application in postmenopausal women referred to...

Although several decision rules have been developed to identify postmenopausal women who may be selected for dual-energy x-ray absorptiometry measurements, information on their utility in a clinical setting is scarce. We evaluated the utility of 4 previously validated decision rules in a large group of Spanish postmenopausal women referred to a bone densitometry unit.

We reviewed the data on 665 postmenopausal women (mean age 54.2 +/- 5.4 yrs). We selected the 4 decision rules that could be applied with the information that was available: the Osteoporosis Risk Assessment Instrument (ORAI), Osteoporosis Self-Assessment Tool (OST), Osteoporosis Index of Risk (OSIRIS), and Body Weight Criterion (BWC). The sensitivity, specificity, and predictive values of each decision rule were determined.

The ORAI would recommend 45% of women for bone mineral density (BMD) testing, OST 46%, OSIRIS 37%, and BWC 70%. Sensitivity values obtained in the overall series were 64.1% for the ORAI, 69.2% for OST, 58.1% for OSIRIS, and 83.8% for BWC. The sensitivity increased progressively with age. The negative predictive value in the overall series was 88.5% for ORAI, 89.9% for OST, 88.4% for OSIRIS, and 90.6% for BWC.

In a complementary way with previous studies in older women, where decision rules were valuable to identify the majority of women likely to have osteoporosis, our data indicate that in younger postmenopausal women, decision rules are useful as a screening method to rule out the presence of osteoporosis and the need for BMD scanning.