The PASI (psoriasis area and severity index) can be used to evaluate the severity of psoriasis at a given time. Plotting a patient’s PASI over time gives a curve reflecting the severity of the psoriasis over the period. E-PAP (evaluation for prognosis with averaged PASI) is the average area under the curve for this plot. This can be helpful in monitoring the long-term follow-up of patients under treatment.
