"The precise definition of intermediate probability (i.e., between 10% and 90%, 20% and 80%, or 30% and 70%) is somewhat arbitrary. In addition to these boundaries, other factors are important in the decision to refer a patient to testing, including the degree of uncertainty acceptable to the physician and patient; the likelihood of an alternative diagnosis; the accuracy of the diagnostic test selected (i.e., sensitivity and specificity), test reliability, procedural cost, and the potential risks of further testing; and the benefits and risks of treatment in the absence of additional testing"