Severity measure
Although severity measure is an everyday way of speaking about the output of the device, keep in mind that what the device outputs is quantifiable data on the intensity, count and extent of clinical signs such as erythema, desquamation, and induration, among others.
Indeed, healthcare practitioners and organisations may use the data output by the device to determine the extent to which a patient is affected, but what the device itself outputs is not the severity. This is appropriately signalled in the output of the device, which follows the FHIR standard when noting that the output is a DiagnosticReport, with a status of preliminary.
Illustrative examples
The JSON blocks on this page are illustrative sample responses, included to show the shape of the data that the device returns. The values inside them, including the values in the metrics object, are examples. They are not statements of the performance of the device and must not be read as performance claims.
Table of contents
Version 2.0
Endpoint
https://ai.legit.health/v2/legit_health/predict
Body Request
If you need to analyse an image whose known condition is atopic dermatitis, you can send a follow up request to the API.
An example of the body of the request can be the following:
{
"requestId": "90925097-820b-403d-a75d-4cd989903df1",
"data": {
"type": "image",
"modality": "clinical",
"operator": "Practitioner",
"bodySite": "ARM_LEFT",
"knownConditionForThisImage": {
"conclusion": "Atopic dermatitis"
},
"subject": {
"identifier": "6ec724a0-6fa3-11eb-a15f-0242ac160004",
"gender": "m",
"height": 175,
"weight": 71,
"birthdate": "1986-10-21",
"generalPractitioner": {
"identifier": "44f89a8c-6f8a-11eb-9c8a-0242ac160004"
},
"managingOrganization": {
"identifier": "b13cd636-327b-11ec-86b0-0242ac180004",
"display": "Hospital Central"
}
},
"scoringSystems": ["ASCORAD_LOCAL", "SCORAD_LOCAL", "DLQI"],
"questionnaireResponse": {
"DLQI": {
"question1": 2,
"question2": 3,
"question3": 1,
"question4": 2,
"question5": 1,
"question6": 2,
"question7": 2,
"question8": 2,
"question9": 3,
"question10": 2
},
"ASCORAD_LOCAL": {
"surfaceValue": 27,
"itchinessScorad": 2,
"sleeplessness": 2
},
"SCORAD_LOCAL": {
"surfaceValue": 27,
"itchinessScorad": 2,
"sleeplessness": 2,
"erythema": 2,
"swelling": 2,
"crusting": 1,
"excoriation": 1,
"lichenification": 1,
"dryness": 1
}
},
"content": "base64 image",
"previousMedia": [
{
"content": "base64 image",
"date": "2022-02-22T12:16:59+01:00"
}
]
}
}
This is the description of the relevant properties of the body request:
bodySiteis the body site code identifying the zone where the photo was taken. The list of admitted codes is provided by Legit.Health on request through support@legit.health.knownConditionForThisImageis set to the codeAtopic dermatitis, so the API will run the specific algorithms related to this pathology.previousMediais not mandatory. It is an array with a set of the previous images of the analysed condition. The AI algorithms use this information to calculate the final report.scoringSystemsis an array with the scoring systems to be calculated. For atopic dermatitis we support:ASCORAD_LOCAL, the automatic version of the SCORAD. See ASCORAD.SCORAD_LOCAL, the SCORAD scoring system calculated at local level.DLQI.
questionnaireResponse. See next section
How to fill questionnaireResponse
The property questionnaireResponse must contain all the mandatory answers to each scoring system specified in the property scoringSystems.
For example, if you want the API to compute the DLQI, questionnaireResponse["DLQI"] must contain the ten values corresponding to the ten questions DLQI has.
Questionnaires for scoring systems
The following snippet contains the questionnaires for each scoring system available for Atopic Dermatitis. To have the device calculate one of them, you must obtain the required answers from the patient or the practitioner.
[
{
"code": "ASCORAD_LOCAL",
"questions": [
{
"code": "surfaceValue",
"label": "Affected area",
"description": "",
"openField": true
},
{
"code": "itchinessScorad",
"label": "Itchiness",
"description": null,
"answers": [
{ "label": "0", "value": "0" },
{ "label": "1", "value": "1" },
{ "label": "2", "value": "2" },
{ "label": "3", "value": "3" },
{ "label": "4", "value": "4" },
{ "label": "5", "value": "5" },
{ "label": "6", "value": "6" },
{ "label": "7", "value": "7" },
{ "label": "8", "value": "8" },
{ "label": "9", "value": "9" },
{ "label": "10", "value": "10" }
],
"openField": false
},
{
"code": "sleeplessness",
"label": "Sleeplessness",
"description": null,
"answers": [
{ "label": "0", "value": "0" },
{ "label": "1", "value": "1" },
{ "label": "2", "value": "2" },
{ "label": "3", "value": "3" },
{ "label": "4", "value": "4" },
{ "label": "5", "value": "5" },
{ "label": "6", "value": "6" },
{ "label": "7", "value": "7" },
{ "label": "8", "value": "8" },
{ "label": "9", "value": "9" },
{ "label": "10", "value": "10" }
],
"openField": false
}
]
},
{
"code": "DLQI",
"questions": [
{
"code": "question1",
"label": "Over the last week, how itchy, sore, painful or stinging has your skin been?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question2",
"label": "Over the last week, how embarrassed or self conscious have you been because of your skin?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question3",
"label": "Over the last week, how much has your skin interfered with you going shopping or looking after your home or garden? ",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question4",
"label": "Over the last week, how much has your skin influenced the clothes you wear?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question5",
"label": "Over the last week, how much has your skin affected any social or leisure activities?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question6",
"label": "Over the last week, how much has your skin made it difficult for you to do any sport?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question7",
"label": "Over the last week, how much has your skin prevented you from working or studying?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question8",
"label": "Over the last week, how much has your skin created problems with your partner or any of your close friends or relatives?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question9",
"label": "Over the last week, how much has your skin caused any sexual difficulties?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
},
{
"code": "question10",
"label": "Over the last week, how much of a problem has the treatment for your skin been, for example by making your home messy, or by taking up time?",
"description": null,
"answers": [
{ "label": "Not at all", "value": "0" },
{ "label": "A little", "value": "1" },
{ "label": "A lot", "value": "2" },
{ "label": "Very much", "value": "3" }
],
"openField": false
}
]
},
{
"code": "SCORAD_LOCAL",
"questions": [
{
"code": "surfaceValue",
"label": "Affected area",
"description": "",
"openField": true
},
{
"code": "erythema",
"label": "Redness",
"description": null,
"answers": [
{ "label": "None", "value": "0" },
{ "label": "Mild", "value": "1" },
{ "label": "Moderate", "value": "2" },
{ "label": "Severe", "value": "3" }
],
"openField": false
},
{
"code": "swelling",
"label": "Swelling",
"description": null,
"answers": [
{ "label": "None", "value": "0" },
{ "label": "Mild", "value": "1" },
{ "label": "Moderate", "value": "2" },
{ "label": "Severe", "value": "3" }
],
"openField": false
},
{
"code": "crusting",
"label": "Crusting",
"description": null,
"answers": [
{ "label": "None", "value": "0" },
{ "label": "Mild", "value": "1" },
{ "label": "Moderate", "value": "2" },
{ "label": "Severe", "value": "3" }
],
"openField": false
},
{
"code": "excoriation",
"label": "Excoriation",
"description": null,
"answers": [
{ "label": "None", "value": "0" },
{ "label": "Mild", "value": "1" },
{ "label": "Moderate", "value": "2" },
{ "label": "Severe", "value": "3" }
],
"openField": false
},
{
"code": "lichenification",
"label": "Lichenification",
"description": null,
"answers": [
{ "label": "None", "value": "0" },
{ "label": "Mild", "value": "1" },
{ "label": "Moderate", "value": "2" },
{ "label": "Severe", "value": "3" }
],
"openField": false
},
{
"code": "dryness",
"label": "Dryness",
"description": null,
"answers": [
{ "label": "None", "value": "0" },
{ "label": "Mild", "value": "1" },
{ "label": "Moderate", "value": "2" },
{ "label": "Severe", "value": "3" }
],
"openField": false
},
{
"code": "itchinessScorad",
"label": "Itchiness",
"description": null,
"answers": [
{ "label": "0", "value": "0" },
{ "label": "1", "value": "1" },
{ "label": "2", "value": "2" },
{ "label": "3", "value": "3" },
{ "label": "4", "value": "4" },
{ "label": "5", "value": "5" },
{ "label": "6", "value": "6" },
{ "label": "7", "value": "7" },
{ "label": "8", "value": "8" },
{ "label": "9", "value": "9" },
{ "label": "10", "value": "10" }
],
"openField": false
},
{
"code": "sleeplessness",
"label": "Sleeplessness",
"description": null,
"answers": [
{ "label": "0", "value": "0" },
{ "label": "1", "value": "1" },
{ "label": "2", "value": "2" },
{ "label": "3", "value": "3" },
{ "label": "4", "value": "4" },
{ "label": "5", "value": "5" },
{ "label": "6", "value": "6" },
{ "label": "7", "value": "7" },
{ "label": "8", "value": "8" },
{ "label": "9", "value": "9" },
{ "label": "10", "value": "10" }
],
"openField": false
}
]
}
]
Response
The response shown below is an illustrative example: the values in it, including the values in the metrics object, are examples rather than statements of device performance.
{
"category": [
{
"coding": [
{
"code": "250171008",
"display": "Clinical history and observation finding",
"system": "http://snomed.info/sct"
}
]
}
],
"code": {
"coding": [
{
"code": "10206-1",
"display": "Physical findings of Skin Narrative",
"system": "http://loinc.org"
}
]
},
"detectedModality": "Clinical",
"evolution": {
"domains": {
"ASCORAD_LOCAL": {
"explainabilityMedia": {
"content": "base 64 image",
"detections": null
},
"facets": {
"crusting": {
"intensity": 0,
"value": 0
},
"dryness": {
"intensity": 0,
"value": 0
},
"erythema": {
"intensity": 0,
"value": 0
},
"excoriation": {
"intensity": 0,
"value": 0
},
"lichenification": {
"intensity": 0,
"value": 0
},
"surfaceValue": {
"intensity": 2,
"value": 27
},
"swelling": {
"intensity": 0,
"value": 0
},
"itchinessScorad": {
"intensity": 0,
"value": 0
},
"sleeplessness": {
"intensity": 0,
"value": 0
}
},
"grade": {
"category": "Mild",
"score": 4.486
}
},
"DLQI": {
"explainabilityMedia": {
"content": null,
"detections": null
},
"facets": {
"question1": {
"intensity": null,
"value": 2
},
"question2": {
"intensity": null,
"value": 2
},
"question3": {
"intensity": null,
"value": 2
},
"question4": {
"intensity": null,
"value": 2
},
"question5": {
"intensity": null,
"value": 2
},
"question6": {
"intensity": null,
"value": 2
},
"question7": {
"intensity": null,
"value": 2
},
"question8": {
"intensity": null,
"value": 2
},
"question9": {
"intensity": null,
"value": 2
},
"question10": {
"intensity": null,
"value": 2
}
},
"grade": {
"category": "Very large effect on patient's life",
"score": 20
}
},
"SCORAD_LOCAL": {
"explainabilityMedia": {
"content": null,
"detections": null
},
"facets": {
"crusting": {
"intensity": null,
"value": 0
},
"dryness": {
"intensity": null,
"value": 0
},
"erythema": {
"intensity": null,
"value": 0
},
"excoriation": {
"intensity": null,
"value": 0
},
"lichenification": {
"intensity": 0,
"value": 0
},
"surfaceValue": {
"intensity": null,
"value": 27
},
"swelling": {
"intensity": null,
"value": 0
},
"itchinessScorad": {
"intensity": null,
"value": 0
},
"sleeplessness": {
"intensity": null,
"value": 0
}
},
"grade": {
"category": "Mild",
"score": 4.486
}
}
}
},
"explainabilityMedia": {
"content": "base 64 image",
"modality": "Clinical",
"resourceType": "Media",
"type": "image"
},
"mediaValidity": {
"isValid": true,
"metrics": {
"hasEnoughQuality": true,
"isDermatologyDomain": true
},
"score": 66.0
},
"metrics": {
"category": "calculation",
"resourceType": "DeviceMetric",
"sensitivity": 99.56,
"specificity": 93.99
},
"preliminaryFindings": {
"hasConditionSuspicion": 99.2,
"isMalignantSuspicion": 0,
"isPreMalignantSuspicion": 0.6000000000000001,
"needsBiopsySuspicion": 0,
"needsSpecialistsAttention": 3.86
},
"resourceType": "DiagnosticReport",
"status": "preliminary",
"time": 2.5790834426879883,
"conclusions": [
{
"code": {
"code": "",
"codeSystem": "ICD-11"
},
"name": "Atopic dermatits",
"probability": 98.66
},
{
"code": {
"code": "",
"codeSystem": "ICD-11"
},
"name": "Nonspecific lesion",
"probability": 1.34
}
]
}
Version 2.1
What changed?
Nothing changed in regard to the severity measure. The only change is that, for the diagnostic support feature, you can now send multiple images of the same lesion.
Endpoint
https://ai.legit.health/v2/legit_health/severity_assessment
Body Request
The interaction with the API is the same as version 2.0.
Response
The response has been updated, but primarily in terms of the information provided. Specifically, version 2.1 does not include diagnostic support details in the output. The response shown below is an illustrative example: the values in it, including the values in the metrics object, are examples rather than statements of device performance.
{
"category": [
{
"coding": [
{
"code": "250171008",
"display": "Clinical history and observation finding",
"system": "http://snomed.info/sct"
}
]
}
],
"code": {
"coding": [
{
"code": "10206-1",
"display": "Physical findings of Skin Narrative",
"system": "http://loinc.org"
}
]
},
"detectedModality": "Clinical",
"evolution": {
"domains": {
"ASCORAD_LOCAL": {
"explainabilityMedia": {
"content": "base 64 image",
"detections": null
},
"facets": {
"crusting": {
"intensity": 0,
"value": 0
},
"dryness": {
"intensity": 0,
"value": 0
},
"erythema": {
"intensity": 0,
"value": 0
},
"excoriation": {
"intensity": 0,
"value": 0
},
"lichenification": {
"intensity": 0,
"value": 0
},
"surfaceValue": {
"intensity": 2,
"value": 27
},
"swelling": {
"intensity": 0,
"value": 0
},
"itchinessScorad": {
"intensity": 0,
"value": 0
},
"sleeplessness": {
"intensity": 0,
"value": 0
}
},
"grade": {
"category": "Mild",
"score": 4.486
}
},
"DLQI": {
"explainabilityMedia": {
"content": null,
"detections": null
},
"facets": {
"question1": {
"intensity": null,
"value": 2
},
"question2": {
"intensity": null,
"value": 2
},
"question3": {
"intensity": null,
"value": 2
},
"question4": {
"intensity": null,
"value": 2
},
"question5": {
"intensity": null,
"value": 2
},
"question6": {
"intensity": null,
"value": 2
},
"question7": {
"intensity": null,
"value": 2
},
"question8": {
"intensity": null,
"value": 2
},
"question9": {
"intensity": null,
"value": 2
},
"question10": {
"intensity": null,
"value": 2
}
},
"grade": {
"category": "Very large effect on patient's life",
"score": 20
}
},
"SCORAD_LOCAL": {
"explainabilityMedia": {
"content": null,
"detections": null
},
"facets": {
"crusting": {
"intensity": null,
"value": 0
},
"dryness": {
"intensity": null,
"value": 0
},
"erythema": {
"intensity": null,
"value": 0
},
"excoriation": {
"intensity": null,
"value": 0
},
"lichenification": {
"intensity": 0,
"value": 0
},
"surfaceValue": {
"intensity": null,
"value": 27
},
"swelling": {
"intensity": null,
"value": 0
},
"itchinessScorad": {
"intensity": null,
"value": 0
},
"sleeplessness": {
"intensity": null,
"value": 0
}
},
"grade": {
"category": "Mild",
"score": 4.486
}
}
}
},
"mediaValidity": {
"isValid": true,
"metrics": {
"hasEnoughQuality": true,
"isDermatologyDomain": true
},
"score": 66.0
},
"resourceType": "DiagnosticReport",
"status": "preliminary",
"time": 2.5790834426879883
}