A method, system and computer program product are provided for evaluating whether an oscillometric signal representative of pressure oscillations in the vasculature of a patient is associated with special conditions that may lead to inadvertently identifying the signal as being indicative of peripheral arterial disease or non-analyzable. In one embodiment, the method includes obtaining an oscillometric signal at a location on an extremity of the patient, determining a ratio using a value associated with a first frequency component of the oscillometric signal and a value associated with a second frequency component of the oscillometric signal, comparing the ratio to a threshold value, associating a first diagnostic class with the oscillometric signal when a first outcome results from comparing the ratio to a threshold value, and associating a second diagnostic class with the oscillometric signal when a second outcome results from comparing the ratio to a threshold value.