Emergency · LIVE
Eczema Area and Severity Index (EASI)
EASI
Compute Hanifin 2001 EASI from four body regions. For each region the caller assigns area 0-6 and four intensity signs (erythema, edema/papulation, excoriation, lichenification) each 0-3. Region score = (sum of 4 signs) × area × adult weight. Total EASI is the sum (max 72).
Markdown: /docs/easi.md · Canonical: https://magentlab.com/docs/easi
Not a medical device. Not a diagnosis, dose, or listing recommendation.
What it computes
Compute Hanifin 2001 EASI from four body regions. For each region the caller assigns area 0-6 and four intensity signs (erythema, edema/papulation, excoriation, lichenification) each 0-3. Region score = (sum of 4 signs) × area × adult weight. Total EASI is the sum (max 72).
When to use
When an agent already has caller-assigned Hanifin 2001 EASI region area and sign integers and needs the published adult-weight total. magent does not examine the skin, diagnose atopic dermatitis, apply pediatric region weights, or assign Investigator Global Assessment or later mild-moderate-severe EASI cutoffs.
When not to use
- Not a medical device and not a diagnosis of atopic dermatitis or a treatment order. magent does not examine the skin. Each area (0-6) and sign (0-3) is a caller-assigned integer.
- magent uses the published adult area weights (head/neck 0.1, upper extremities 0.2, trunk 0.3, lower extremities 0.4). It does not apply later pediatric (<8 years) head/neck 0.2 and lower-extremity 0.3 multipliers.
- Hanifin 2001 published no Investigator Global Assessment or mild-moderate-severe EASI cutoffs. magent returns the numeric EASI only.
- Each sign is a caller-assigned integer 0-3. magent does not accept half-point grades.
Formula
EASI = 0.1*(head_neck_erythema + head_neck_edema_papulation + head_neck_excoriation + head_neck_lichenification)*head_neck_area + 0.2*(upper_extremities_erythema + upper_extremities_edema_papulation + upper_extremities_excoriation + upper_extremities_lichenification)*upper_extremities_area + 0.3*(trunk_erythema + trunk_edema_papulation + trunk_excoriation + trunk_lichenification)*trunk_area + 0.4*(lower_extremities_erythema + lower_extremities_edema_papulation + lower_extremities_excoriation + lower_extremities_lichenification)*lower_extremities_area; each area integer 0-6 (0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%); each sign integer 0-3 (0 none, 1 mild, 2 moderate, 3 severe); adult region weights head/neck 0.1, upper extremities 0.2, trunk 0.3, lower extremities 0.4; max 72; magent uses these adult weights only; this paper published no Investigator Global Assessment or mild-moderate-severe EASI cutoffs
Citation
- Authors
- Hanifin JM, Thurston M, Omoto M, Cherill R, Tofte SJ, Graeber M
- Source
- Exp Dermatol. 2001;10(1):11-18
Worked example
All zeros
Given:
head_neck_area=0head_neck_edema_papulation=0head_neck_erythema=0head_neck_excoriation=0head_neck_lichenification=0lower_extremities_area=0lower_extremities_edema_papulation=0lower_extremities_erythema=0lower_extremities_excoriation=0lower_extremities_lichenification=0trunk_area=0trunk_edema_papulation=0trunk_erythema=0trunk_excoriation=0trunk_lichenification=0upper_extremities_area=0upper_extremities_edema_papulation=0upper_extremities_erythema=0upper_extremities_excoriation=0upper_extremities_lichenification=0
- every region area 0 and every sign 0 as assigned by the caller
- each region score = 0; EASI = 0 (max 72). This paper published no IGA or mild-moderate-severe EASI cutoff.
All regions at published maximum
Given:
head_neck_area=6head_neck_edema_papulation=3head_neck_erythema=3head_neck_excoriation=3head_neck_lichenification=3lower_extremities_area=6lower_extremities_edema_papulation=3lower_extremities_erythema=3lower_extremities_excoriation=3lower_extremities_lichenification=3trunk_area=6trunk_edema_papulation=3trunk_erythema=3trunk_excoriation=3trunk_lichenification=3upper_extremities_area=6upper_extremities_edema_papulation=3upper_extremities_erythema=3upper_extremities_excoriation=3upper_extremities_lichenification=3
- each area 6 and each of the four signs 3 as assigned by the caller
- head/neck 12×6×0.1 = 7.2; upper extremities 12×6×0.2 = 14.4; trunk 12×6×0.3 = 21.6; lower extremities 12×6×0.4 = 28.8; EASI = 72 (max 72). No IGA or severity band.
Also searched as
- EASI
- Eczema Area and Severity Index
- Hanifin EASI
- EASI score
- atopic dermatitis EASI
- eczema severity index
- Hanifin 2001 EASI
- AD area and severity
Try
Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.
Full URL: https://api.magentlab.com/api/calc/easi?head_neck_area=0&head_neck_erythema=0&head_neck_edema_papulation=0&head_neck_excoriation=0&head_neck_lichenification=0&upper_extremities_area=0&upper_extremities_erythema=0&upper_extremities_edema_papulation=0&upper_extremities_excoriation=0&upper_extremities_lichenification=0&trunk_area=0&trunk_erythema=0&trunk_edema_papulation=0&trunk_excoriation=0&trunk_lichenification=0&lower_extremities_area=0&lower_extremities_erythema=0&lower_extremities_edema_papulation=0&lower_extremities_excoriation=0&lower_extremities_lichenification=0
Call
Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params
return HTTP 400 before any quote or charge.
curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/easi?head_neck_area=0&head_neck_erythema=0&head_neck_edema_papulation=0&head_neck_excoriation=0&head_neck_lichenification=0&upper_extremities_area=0&upper_extremities_erythema=0&upper_extremities_edema_papulation=0&upper_extremities_excoriation=0&upper_extremities_lichenification=0&trunk_area=0&trunk_erythema=0&trunk_edema_papulation=0&trunk_excoriation=0&trunk_lichenification=0&lower_extremities_area=0&lower_extremities_erythema=0&lower_extremities_edema_papulation=0&lower_extremities_excoriation=0&lower_extremities_lichenification=0"
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
head_neck_area |
integer | required · 0, 1, 2, 3, 4, 5, 6 | Caller-assigned Hanifin 2001 EASI area of involvement for this body region (integer 0-6): 0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%. magent does not examine the skin. |
head_neck_erythema |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI erythema for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
head_neck_edema_papulation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI edema/papulation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
head_neck_excoriation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI excoriation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
head_neck_lichenification |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI lichenification for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
upper_extremities_area |
integer | required · 0, 1, 2, 3, 4, 5, 6 | Caller-assigned Hanifin 2001 EASI area of involvement for this body region (integer 0-6): 0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%. magent does not examine the skin. |
upper_extremities_erythema |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI erythema for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
upper_extremities_edema_papulation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI edema/papulation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
upper_extremities_excoriation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI excoriation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
upper_extremities_lichenification |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI lichenification for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
trunk_area |
integer | required · 0, 1, 2, 3, 4, 5, 6 | Caller-assigned Hanifin 2001 EASI area of involvement for this body region (integer 0-6): 0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%. magent does not examine the skin. |
trunk_erythema |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI erythema for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
trunk_edema_papulation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI edema/papulation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
trunk_excoriation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI excoriation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
trunk_lichenification |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI lichenification for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
lower_extremities_area |
integer | required · 0, 1, 2, 3, 4, 5, 6 | Caller-assigned Hanifin 2001 EASI area of involvement for this body region (integer 0-6): 0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%. magent does not examine the skin. |
lower_extremities_erythema |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI erythema for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
lower_extremities_edema_papulation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI edema/papulation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
lower_extremities_excoriation |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI excoriation for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
lower_extremities_lichenification |
integer | required · 0, 1, 2, 3 | Caller-assigned Hanifin 2001 EASI lichenification for this region (integer 0-3): 0 none, 1 mild, 2 moderate, 3 severe. magent does not examine the skin. |
Bulk (POST)
POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.
- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
- The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
- HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
- Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
- x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.
Example request (fixture)
{
"items": [
{
"head_neck_area": "0",
"head_neck_edema_papulation": "0",
"head_neck_erythema": "0",
"head_neck_excoriation": "0",
"head_neck_lichenification": "0",
"lower_extremities_area": "0",
"lower_extremities_edema_papulation": "0",
"lower_extremities_erythema": "0",
"lower_extremities_excoriation": "0",
"lower_extremities_lichenification": "0",
"trunk_area": "0",
"trunk_edema_papulation": "0",
"trunk_erythema": "0",
"trunk_excoriation": "0",
"trunk_lichenification": "0",
"upper_extremities_area": "0",
"upper_extremities_edema_papulation": "0",
"upper_extremities_erythema": "0",
"upper_extremities_excoriation": "0",
"upper_extremities_lichenification": "0"
},
{
"head_neck_area": "0",
"head_neck_edema_papulation": "0",
"head_neck_erythema": "0",
"head_neck_excoriation": "0",
"head_neck_lichenification": "0",
"lower_extremities_area": "0",
"lower_extremities_edema_papulation": "0",
"lower_extremities_erythema": "0",
"lower_extremities_excoriation": "0",
"lower_extremities_lichenification": "0",
"trunk_area": "0",
"trunk_edema_papulation": "0",
"trunk_erythema": "0",
"trunk_excoriation": "0",
"trunk_lichenification": "0",
"upper_extremities_area": "0",
"upper_extremities_edema_papulation": "0",
"upper_extremities_erythema": "0",
"upper_extremities_excoriation": "0",
"upper_extremities_lichenification": "0"
}
]
}
Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.
Example 200 (fixture)
{
"count": 2,
"path": "/api/calc/easi",
"items": [
{
"components": [
{
"value": 0,
"factor": "head_neck",
"weight": 0.1,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "upper_extremities",
"weight": 0.2,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "trunk",
"weight": 0.3,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "lower_extremities",
"weight": 0.4,
"points": 0.0,
"present": true,
"area": 0
}
],
"disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
"citation": {
"authors": "Hanifin JM, Thurston M, Omoto M, Cherill R, Tofte SJ, Graeber M",
"doi": "10.1034/j.1600-0625.2001.100102.x",
"id": "hanifin-2001",
"pmid": "11168575",
"source": "Exp Dermatol. 2001;10(1):11-18",
"title": "The eczema area and severity index (EASI): assessment of reliability in atopic dermatitis"
},
"formula": "easi",
"formula_expression": "EASI = 0.1*(head_neck_erythema + head_neck_edema_papulation + head_neck_excoriation + head_neck_lichenification)*head_neck_area + 0.2*(upper_extremities_erythema + upper_extremities_edema_papulation + upper_extremities_excoriation + upper_extremities_lichenification)*upper_extremities_area + 0.3*(trunk_erythema + trunk_edema_papulation + trunk_excoriation + trunk_lichenification)*trunk_area + 0.4*(lower_extremities_erythema + lower_extremities_edema_papulation + lower_extremities_excoriation + lower_extremities_lichenification)*lower_extremities_area; each area integer 0-6 (0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%); each sign integer 0-3 (0 none, 1 mild, 2 moderate, 3 severe); adult region weights head/neck 0.1, upper extremities 0.2, trunk 0.3, lower extremities 0.4; max 72; magent uses these adult weights only; this paper published no Investigator Global Assessment or mild-moderate-severe EASI cutoffs",
"max_score": 72,
"score": 0.0,
"head_neck_score": 0.0,
"lower_extremities_score": 0.0,
"trunk_score": 0.0,
"upper_extremities_score": 0.0
},
{
"components": [
{
"value": 0,
"factor": "head_neck",
"weight": 0.1,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "upper_extremities",
"weight": 0.2,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "trunk",
"weight": 0.3,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "lower_extremities",
"weight": 0.4,
"points": 0.0,
"present": true,
"area": 0
}
],
"disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
"citation": {
"authors": "Hanifin JM, Thurston M, Omoto M, Cherill R, Tofte SJ, Graeber M",
"doi": "10.1034/j.1600-0625.2001.100102.x",
"id": "hanifin-2001",
"pmid": "11168575",
"source": "Exp Dermatol. 2001;10(1):11-18",
"title": "The eczema area and severity index (EASI): assessment of reliability in atopic dermatitis"
},
"formula": "easi",
"formula_expression": "EASI = 0.1*(head_neck_erythema + head_neck_edema_papulation + head_neck_excoriation + head_neck_lichenification)*head_neck_area + 0.2*(upper_extremities_erythema + upper_extremities_edema_papulation + upper_extremities_excoriation + upper_extremities_lichenification)*upper_extremities_area + 0.3*(trunk_erythema + trunk_edema_papulation + trunk_excoriation + trunk_lichenification)*trunk_area + 0.4*(lower_extremities_erythema + lower_extremities_edema_papulation + lower_extremities_excoriation + lower_extremities_lichenification)*lower_extremities_area; each area integer 0-6 (0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%); each sign integer 0-3 (0 none, 1 mild, 2 moderate, 3 severe); adult region weights head/neck 0.1, upper extremities 0.2, trunk 0.3, lower extremities 0.4; max 72; magent uses these adult weights only; this paper published no Investigator Global Assessment or mild-moderate-severe EASI cutoffs",
"max_score": 72,
"score": 0.0,
"head_neck_score": 0.0,
"lower_extremities_score": 0.0,
"trunk_score": 0.0,
"upper_extremities_score": 0.0
}
]
}
Response
| Field | Type | Description |
|---|---|---|
formula |
string | easi |
formula_expression |
string | Exact expression used |
score |
number | Hanifin 2001 EASI total from four adult-weighted regions (0-72) |
max_score |
integer | Always 72 |
head_neck_score |
number | Head/neck region: (sum of 4 signs) × area × 0.1 |
upper_extremities_score |
number | Upper extremities region: (sum of 4 signs) × area × 0.2 |
trunk_score |
number | Trunk region: (sum of 4 signs) × area × 0.3 |
lower_extremities_score |
number | Lower extremities region: (sum of 4 signs) × area × 0.4 |
components |
array | Per-region caller-assigned EASI contribution |
citation |
object | Hanifin et al. Exp Dermatol 2001 citation |
disclaimer |
string | Not-a-device notice |
Example JSON
Machine form of the same example. Frozen fixture. Not a live lookup.
{
"components": [
{
"value": 0,
"factor": "head_neck",
"weight": 0.1,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "upper_extremities",
"weight": 0.2,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "trunk",
"weight": 0.3,
"points": 0.0,
"present": true,
"area": 0
},
{
"value": 0,
"factor": "lower_extremities",
"weight": 0.4,
"points": 0.0,
"present": true,
"area": 0
}
],
"disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
"citation": {
"authors": "Hanifin JM, Thurston M, Omoto M, Cherill R, Tofte SJ, Graeber M",
"doi": "10.1034/j.1600-0625.2001.100102.x",
"id": "hanifin-2001",
"pmid": "11168575",
"source": "Exp Dermatol. 2001;10(1):11-18",
"title": "The eczema area and severity index (EASI): assessment of reliability in atopic dermatitis"
},
"formula": "easi",
"formula_expression": "EASI = 0.1*(head_neck_erythema + head_neck_edema_papulation + head_neck_excoriation + head_neck_lichenification)*head_neck_area + 0.2*(upper_extremities_erythema + upper_extremities_edema_papulation + upper_extremities_excoriation + upper_extremities_lichenification)*upper_extremities_area + 0.3*(trunk_erythema + trunk_edema_papulation + trunk_excoriation + trunk_lichenification)*trunk_area + 0.4*(lower_extremities_erythema + lower_extremities_edema_papulation + lower_extremities_excoriation + lower_extremities_lichenification)*lower_extremities_area; each area integer 0-6 (0 none, 1 <10%, 2 10-29%, 3 30-49%, 4 50-69%, 5 70-89%, 6 90-100%); each sign integer 0-3 (0 none, 1 mild, 2 moderate, 3 severe); adult region weights head/neck 0.1, upper extremities 0.2, trunk 0.3, lower extremities 0.4; max 72; magent uses these adult weights only; this paper published no Investigator Global Assessment or mild-moderate-severe EASI cutoffs",
"max_score": 72,
"score": 0.0,
"head_neck_score": 0.0,
"lower_extremities_score": 0.0,
"trunk_score": 0.0,
"upper_extremities_score": 0.0
}
Client errors (HTTP 400)
Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.
| HTTP | Code | When |
|---|---|---|
| 400 | invalid_easi |
EASI needs Hanifin 2001 region area (0-6) and erythema, edema/papulation, excoriation, and lichenification (0-3) for each region. Returned before settlement; you are not charged. |
| 400 | invalid_items |
POST body must be a JSON object with only an items array Returned before settlement; you are not charged. |
| 400 | invalid_item_count |
items must be an array of 1 to 25 objects Returned before settlement; you are not charged. |
| 400 | invalid_item |
each items entry must be a JSON object Returned before settlement; you are not charged. |
Related tools
- UAS — Sum Młynek 2008 EAACI/GA2LEN/EDF urticaria activity score over seven consecutive days: each day wheals 0-3 plus pruritus 0-3 (daily UAS 0-6). Return UAS7 (0-42) and mean_daily_uas. This paper published no UAS7 activity bands.
Payment
Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. Unpaid valid requests return HTTP 402 with a base64
PAYMENT-REQUIRED
header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake
and shared payment errors: Payments.
Stdio MCP: /docs/mcp.
Guarantees
- HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
- exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
- HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.