Psychophysiological responses in the diagnosis of posttraumatic stress disorder in Vietnam veterans.

In one sample of 104 male Vietnam combat veterans, we found that five heart rate parameters from a psychophysiological assessment could correctly discriminate 75% of the sample into those with PTSD and those without it. Using a stepwise approach, we found adding 10 blood pressure parameters increased discrimination to 80%, while adding five parameters from frontal electromyograms did not increase discrimination. Cross-validation of the heart rate parameters on a new sample of 96 veterans resulted in 83% correct discrimination.