Do we need randomized controlled clinical trials to evaluate the clinical impact of breast MR imaging?

MR imaging of the breast has been shown to identify breast cancers that have gone undetected by mammography. There are a number of potential designs that can be used to further evaluate breast MR imaging, particularly with respect its impact on clinical care. Determination of whether using breast MR imaging to screen healthy individuals for breast cancer actually reduces breast cancer-specific mortality--and whether this can be accomplished at an acceptable cost--probably requires randomized, controlled clinical.