VASI

Vitiligo Area Scoring Index

What is VASI

The Vitiligo Area Scoring Index (VASI) quantifies vitiligo as depigmented area weighted by the degree of depigmentation. It was introduced by I. Hamzavi et al. in 2004 and is now the main efficacy outcome in vitiligo trials, including those of ruxolitinib cream (F-VASI75).

How it is calculated

VASI = Σ (area of each body region in patient hand units × degree of depigmentation). One hand unit — the patient's palm with fingers — is about 1% of body surface area. Degree of depigmentation: 100% — no pigment; 90% — specks of pigment; 75% — depigmented area exceeds pigmented; 50% — equal; 25% — pigmented area exceeds depigmented; 10% — only specks of depigmentation.

How to read the result

VASI has no severity bands — it is compared with baseline. Treatment response: VASI50 — at least 50% improvement, VASI75 — at least 75%, VASI90 — near-complete repigmentation.

Using the calculator

Four methods lead to the same total: “Hand units” — the classic Hamzavi method; “% of zone” — the involved share of each of 32 chart zones; “Reference images” — comparison with pictures of the zone at known percentages; “Drawing” — lesions are painted on the chart. In children, zone areas follow the Lund–Browder chart. The report prints on one A4 page.

Questions and answers

What is the difference between T-VASI and F-VASI?

T-VASI covers the whole body surface (0–100); F-VASI covers the face only (up to 3 in adults). Trials report them separately, for example F-VASI75 and T-VASI50.

What does VASI75 mean?

A reduction in VASI of at least 75% from the pre-treatment baseline.

Are patient data stored on the site?

No. Everything stays in your browser; nothing is sent to the server. On a shared computer, press “New examination” after the visit.

References

  1. Hamzavi I, Jain H, McLean D, et al. Parametric modeling of narrowband UV-B phototherapy for vitiligo using a novel quantitative tool: the Vitiligo Area Scoring Index. Arch Dermatol. 2004;140(6):677–683.
  2. Rosmarin D, Passeron T, Pandya AG, et al. Two phase 3, randomized, controlled trials of ruxolitinib cream for vitiligo. N Engl J Med. 2022;387(16):1445–1455.