Authors' objectives:

The aim of this report was to determine whether the available evidence demonstrates that screening for vertebral fractures using dual x-ray absorptiometry (DXA) improves selection of patients for treatment and consequently reduces risk of future fractures. As there is no direct evidence to show that such screening improves outcomes, this Assessment sought indirect evidence that: 1) vertebral assessment screening using DXA accurately identifies vertebral fractures in the population of patients not diagnosed as osteoporotic by bone mineral density (BMD); and 2) adding vertebral assessment screening using DXA to BMD screening yields additional patients who will benefit from pharmacologic treatment.

Authors' results and conclusions: There is insufficient evidence that the test accurately detects fractures in the population of interest, individuals without osteoporosis who have no symptoms of vertebral fracture. In studies ranging in sample size from 66 to 161 patients, the sensitivity for detecting vertebral fractures ranged from 54% to 72% using the vertebrae as the unit of analysis and 77% to 95% using the patient as the unit of analysis. Specificities ranged from 94% to 99% using the vertebrae as the unit of analysis and 88% to 94% using the patient as the unit of analysis. However, 2 of the studies included only patients with known osteoporosis. The study showing the highest sensitivity may be biased by selective verification. The only study that included a sample not known to be osteoporotic showed the lowest sensitivity for fracture at 54%.

Authors' recommendations: Conclusions about the utility of the test, given its diagnostic characteristics, must be placed in context of the clinical use of the test in making treatment decisions. At present, the diagnostic performance of vertebral fracture assessment using DXA has not been adequately evaluated in the population of interest. However, the clinical context of osteoporosis screening and fracture prevention is evolving. Recent publications of large trials of pharmacologic treatments for osteoporosis suggest that pharmacologic treatment also benefits for subjects with osteopenia. Thus, the threshold for treatment may currently be in flux, and it is unknown whether vertebral fracture assessment using DXA would yield a population of patients that would not otherwise have been treated based on BMD alone. Based on the available evidence, the Blue Cross and Blue Shield Association Medical Advisory Panel made the following judgments about whether screening using vertebral assessment using DXA meets the Blue Cross and Blue Shield Association Technology Evaluation Center (TEC) criteria. 1. The technology must have final approval from the appropriate governmental regulatory bodies. Many dual energy radiographic absorptiometry (DEXA or DXA) devices have received 510(k) marketing clearance from the U.S. Food and Drug Administration (FDA). To perform vertebral fracture assessment on the DXA devices, additional software is needed and it must have 510(k) marketing clearance from the FDA as well. Some examples of vertebral fracture assessment application packages that have received 510(k) marketing clearance are GE LUNAR Corporation's Dual Energy Vertebral Assessment (DVA) (previously known as Lateral Vertebral Assessment or LVA), and Hologic's Instant Vertebral Assessment or IVA. 2. The scientific evidence must permit conclusions concerning the effect of the technology on health outcomes. Current evidence consists of studies examining the diagnostic sensitivity and specificity of vertebral assessment compared to plain X-ray. The populations evaluated in these studies were osteoporotic and may not generalize to the population subject to proposed screening with vertebral assessment. Thus, there is insufficient evidence of the performance characteristics of vertebral assessment in the population of interest. Without accurate knowledge of the performance characteristics of the test, it is impossible to project the outcomes of the patients based on what clinical actions would have taken place, given a specific BMD and vertebral assessment result. 3. The technology must improve the net health outcome. Given the uncertain test performance characteristics of vertebral assessment, it is uncertain that, on the whole, patients' health outcomes would be improved. 4. The technology must be as beneficial as any established alternatives. The evidence does not permit conclusions as to whether screening for vertebral fracture using DXA is as beneficial as established alternatives. 5. The improvement must be attainable outside the investigational settings. Whether screening for vertebral fracture using DXA improves the net health outcome has not been established in the investigational settings. Based on the above, screening for vertebral fracture using DXA does not meet the TEC criteria.

Authors' methods: Review

Project Status: Completed

URL for project: http://www.bcbs.com/blueresources/tec/contact-tec.html

Year Published: 2006

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: BlueCross BlueShield Association

Contact Address: BlueCross BlueShield Association, Technology Evaluation Center, 225 North Michigan Ave, Chicago, Illinois, USA. Tel: 888 832 4321

Contact Name: tec@bcbsa.com

Contact Email: tec@bcbsa.com

Copyright: BlueCross BlueShield Association (BCBS)