# 4AT Delirium Screening Score Calculator

> 4AT Delirium Screening Score Calculator is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Computes the Bellelli 2014 4AT score for cognitive impairment and delirium screening from four caller-assigned clinical items

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/4at
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/4at-delirium-screening-score-calculator-3bcc6657
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_pXQo_XTojCZ8LJ0QfT29_

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability 4at-delirium-screening-score-calculator-3bcc6657
```

Example prompt: Calculate the 4AT delirium score for a patient whose alertness is normal, AMT4 mistake count is 1, attention score is 2 (untestable), and there is an acute change in mental status — so acute_change is true.

## When to prefer this

Use this endpoint when you need to compute the validated Bellelli 2014 4AT rapid clinical test score from pre-assessed clinical observations, and you want a fast, cheap, deterministic arithmetic result with banded interpretation. Prefer this over manual calculation to avoid arithmetic errors. Note this is a screening tool only, not a diagnosis — and the caller must supply all four item scores themselves from their own clinical observations.

## Known failure modes

- Missing required query parameters (alertness, amt4, attention, acute_change) returns a validation error
- Invalid enum values for alertness (not 'normal'/'abnormal') or integer out of range for amt4/attention return bad request
- Payment not included or insufficient USDC triggers x402 payment-required error
- Caller supplying actual patient identifiers (DOB, age) which are not collected and irrelevant to this API

## How this service works

4AT (Bellelli 2014): alertness (normal 0, abnormal 4) + AMT4 mistake count 0/1/2 + attention 0/1/2 + acute change or fluctuation (false 0, true 4). Max 12. Band 0 unlikely, 1–3 possible cognitive impairment, ≥4 possible delirium. Not a delirium or dementia diagnosis. magent does not examine the patient. AMT4 is the caller-assigned mistake count only; this API does not collect age, date of birth, place, or year.

## Output

Returns the numeric 4AT total score (0–12) along with the corresponding clinical band interpretation: 0 = delirium unlikely, 1–3 = possible cognitive impairment, ≥4 = possible delirium. Does not provide a diagnosis.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "alertness",
      "amt4",
      "attention",
      "acute_change"
     ],
     "properties": {
      "amt4": {
       "enum": [
        0,
        1,
        2
       ],
       "type": "integer",
       "description": "Caller-assigned AMT4 mistake count only (Bellelli 2014): 0 mistakes → 0; 1 mistake → 1; ≥2 mistakes or untestable → 2. Integer 0, 1, or 2. This API does not collect age, date of birth, place, or year."
      },
      "alertness": {
       "enum": [
        "normal",
        "abnormal"
       ],
       "type": "string",
       "description": "Bellelli 2014 4AT item 1 as assigned by the caller. normal scores 0; abnormal scores 4. magent does not observe consciousness."
      },
      "attention": {
       "enum": [
        0,
        1,
        2
       ],
       "type": "integer",
       "description": "Bellelli 2014 months-backwards item as assigned by the caller. 0: achieves ≥7 months. 1: starts but <7 months or refuses. 2: untestable. Integer 0, 1, or 2. magent does not run months backwards."
      },
      "acute_change": {
       "type": "boolean",
       "description": "Bellelli 2014 acute change or fluctuating course as assigned by the caller. true scores 4. magent does not take a collateral history."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "path": "/api/calc/4at",
  "count": 2,
  "items": [
   {
    "score": 0,
    "at_band": "unlikely",
    "formula": "4at",
    "citation": {
     "id": "bellelli-2014",
     "doi": "10.1093/ageing/afu021",
     "pmid": "24590568",
     "title": "Validation of the 4AT, a new instrument for rapid delirium screening: a study in 234 hospitalised older people",
     "source": "Age Ageing. 2014;43(4):496-502",
     "authors": "Bellelli G, Morandi A, Davis DH, Mazzola P, Turco R, Gentile S, Ryan T, Cash H, Guerini F, Torpilliesi T, Del Santo F, Trabucchi M, Annoni G, MacLullich AM"
    },
    "max_score": 12,
    "components": [
     {
      "factor": "alertness",
      "points": 0,
      "present": false
     },
     {
      "value": 0,
      "factor": "amt4",
      "points": 0,
      "present": false
     },
     {
      "value": 0,
      "factor": "attention",
      "points": 0,
      "present": false
     },
     {
      "factor": "acute_change",
      "points": 0,
      "present": false
     }
    ],
    "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.",
    "formula_expression": "4AT = alertness (normal 0, abnormal 4) + amt4 (0/1/2) + attention (0/1/2) + acute_change (false 0, true 4); Bellelli 2014; max 12; 0 unlikely, 1-3 possible_cognitive_impairment, ≥4 possible_delirium"
   },
   {
    "score": 0,
    "at_band": "unlikely",
    "formula": "4at",
    "citation": {
     "id": "bellelli-2014",
     "doi": "10.1093/ageing/afu021",
     "pmid": "24590568",
     "title": "Validation of the 4AT, a new instrument for rapid delirium screening: a study in 234 hospitalised older people",
     "source": "Age Ageing. 2014;43(4):496-502",
     "authors": "Bellelli G, Morandi A, Davis DH, Mazzola P, Turco R, Gentile S, Ryan T, Cash H, Guerini F, Torpilliesi T, Del Santo F, Trabucchi M, Annoni G, MacLullich AM"
    },
    "max_score": 12,
    "components": [
     {
      "factor": "alertness",
      "points": 0,
      "present": false
     },
     {
      "value": 0,
      "factor": "amt4",
      "points": 0,
      "present": false
     },
     {
      "value": 0,
      "factor": "attention",
      "points": 0,
      "present": false
     },
     {
      "factor": "acute_change",
      "points": 0,
      "present": false
     }
    ],
    "disclaimer": "Not a medical device. Determinist
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/4at-delirium-screening-score-calculator-3bcc6657/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.magentlab.com](https://www.zero.xyz/host/api.magentlab.com/llms.txt)