# TRISS Survival Probability Calculator (Boyd 1987 MTOS)

> TRISS Survival Probability Calculator (Boyd 1987 MTOS) 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 TRISS probability of survival using Boyd 1987 original MTOS coefficients from caller-supplied RTS, ISS, age, and trauma mechanism.

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/triss
- 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/triss-survival-probability-calculator-boyd-1987-mtos-80b4d24e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bNXjNEZi1SCpS2veUzm19

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 triss-survival-probability-calculator-boyd-1987-mtos-80b4d24e
```

Example prompt: Calculate the TRISS probability of survival for a 45-year-old blunt trauma patient with a caller-assigned RTS of 6.5 and an ISS of 22, using the Boyd 1987 original MTOS coefficients.

## When to prefer this

Use this endpoint when you need a deterministic, citable implementation of the original Boyd 1987 TRISS formula with MTOS coefficients. Prefer it over manual calculation when building trauma registries, audit tools, or clinical decision-support pipelines that require reproducible, publication-traceable survival probability estimates. Do not use for NISS, ASCOT, or Champion 1995 revised coefficient calculations.

## Known failure modes

- Missing required parameter (mechanism, rts, iss, or age) returns an error
- RTS outside 0.0–7.8408 range may yield validation error or out-of-range result
- ISS outside 1–75 integer range rejected
- Age outside 1–120 rejected
- Caller must pre-compute weighted Champion RTS; endpoint does not recode GCS, SBP, or RR
- Payment failure (x402) if USDC not available

## How this service works

TRISS (Boyd 1987): probability of survival from a caller-assigned Champion weighted RTS (0.0-7.8408), ISS (1-75), age (AgeIndex 0 if age < 55 else 1), and blunt or penetrating mechanism using original MTOS coefficients. Deterministic published arithmetic with citation. Not a triage order; not NISS; not ASCOT; not Champion 1995 revised coefficients.

## Output

Returns a TRISS probability of survival (a decimal between 0 and 1) computed from the Boyd 1987 original MTOS logistic regression coefficients using the supplied weighted RTS, ISS, AgeIndex derived from patient age, and blunt or penetrating mechanism flag. The result is deterministic arithmetic with no model inference.

## 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": [
      "mechanism",
      "rts",
      "iss",
      "age"
     ],
     "properties": {
      "age": {
       "type": "integer",
       "description": "Age in whole years 1-120. AgeIndex is 0 if age < 55 and 1 if age >= 55 (Boyd 1987)."
      },
      "iss": {
       "type": "integer",
       "description": "Caller-assigned Injury Severity Score integer 1-75. magent does not compute ISS from AIS here."
      },
      "rts": {
       "type": "number",
       "description": "Caller-assigned Champion weighted Revised Trauma Score (number 0.0-7.8408). magent does not recode GCS, SBP, or respiratory rate here."
      },
      "mechanism": {
       "enum": [
        "blunt",
        "penetrating"
       ],
       "type": "string",
       "description": "blunt or penetrating. Selects the Boyd 1987 original MTOS coefficient set. Required; magent does not infer mechanism."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/triss-survival-probability-calculator-boyd-1987-mtos-80b4d24e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
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