A tool to support the clinical decisions of doctors and health professionals, not for self-diagnosis or self-treatment.
This calculator is inside the patient's file in Clinicato: open it from "Medical tools" while you chart the visit, it fills in from the patient's details and vital signs where they are recorded, and adds its result to the visit's plan in one tap, with the "Medical tools" add-on. Try it in your clinic
Calculator
How it works and when to use it
For each of the four regions erythema, induration and scaling are graded 0 to 4 and the area involved 0 to 6, then the severity sum is multiplied by the area grade and by the region's weight: head 0.1, arms 0.2, trunk 0.3, legs 0.4, for a total from 0 to 72.
By the rule of tens psoriasis is severe when PASI is over 10, or when the body surface area involved or the DLQI is over 10.
Reference: Fredriksson T, Pettersson U. Dermatologica 1978;157:238-44; severity by the "rule of tens" (PASI over 10): Finlay AY. Br J Dermatol 2005;152:861-7
Frequently asked questions
What is PASI used for in follow-up?
To follow the response to treatment, such as a 75% improvement from baseline (PASI 75) in studies of modern treatments.
Is PASI enough to assess a patient?
No, small sensitive areas such as the face, hands and genitals can weigh heavily on a patient's life despite a low score.
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Clinic software for this specialty
Try Clinicato for your clinic
These calculators are free here for everyone, and in Clinicato 49 medical tools work inside the patient's file with the "Medical tools" add-on: filled from the visit and the vital signs, with the result added to the visit's plan, next to appointments, prescriptions and invoices.