<International Circulation>:  Are these intended as alternatives to Guidelines or， as you said， merely extensions of guided therapies?

    Dr Spertus:  They really are an extension of the Guidelines. The Guidelines really say what you ‘can’ do in treating the patient before you and lists， based on available evidence. The Appropriate Use Criteria are targeting ‘what you should do’， given this constellation of symptoms， function， anatomy and ischemia; and what is the likelihood that they will benefit from treatment. It is synergistic with the guidelines， but really has a different application. It is difficult to apply the current Guidelines， as they are written， to look at the quality of decision-making， whereas the Appropriate Use Criteria were specifically designed with that purpose in mind.