Perspective:

This work builds on several prior studies, which were carried out with similar study designs in non-VA hospital settings. Rates of inappropriate testing in these prior studies ranged from 7-24%, comparable to the rates seen in this study. Taken together, these studies suggest that although inappropriate testing is at most moderately prevalent, it remains a significant area for improvement. The observation that rates of inappropriate testing in the VA environment were similar to prior non-VA studies raises concerns that self-referral profit motives and liability concerns may not be the primary drivers of inappropriate testing. However, a few caveats should be noted. First, most prior studies were performed in academic rather than community settings. It is possible that profit and liability concerns may have a lesser influence on referring provider behavior than in the community. Second, many providers in VA environments also practice in non-VA environments and may not compartmentalize their practice patterns based on differences in potential liability. Nonetheless, these results do raise doubt about the potential for policy and regulatory changes to reduce inappropriate testing. Further research into education and training interventions aimed at reducing inappropriate testing may be more fruitful.

Another concern in this particular study is the extremely high rate of PET stress testing. Although PET testing has many advantages over SPECT, exercise stress testing with PET remains extremely challenging and is limited to highly specialized centers. The additional diagnostic and prognostic value of exercise parameters is unavailable with pharmacologic PET testing. The authors acknowledge that seven subjects could have been evaluated with exercise testing without imaging. However, they do not indicate how many subjects could have been evaluated with exercise SPECT testing rather than pharmacologic PET.