Bone mineral density measurements: are they worth while?

Bone mineral density measurements have been criticized on the grounds that they are not a worth-while screening tool. In this paper we argue that bone mineral measurements can be an efficient diagnostic tool even if they are not of proven value for screening. There is complex relationship between the costs of a measurement, the intervention and the predictive value of the test all of which must be accounted for when assessing the value of a bone density measurement. For bone density measurements to be used for screening, a wider evaluation needs to be undertaken compared with that for their use as a diagnostic tool. We address some common objections, for example, that low compliance with screening would undermine efficiency, and show that these are not relevant. Evaluations of screening need to address issues that are likely to affect efficiency.