# Jacobs 1990 Risk of Malignancy Index (RMI) Calculator

> Jacobs 1990 Risk of Malignancy Index (RMI) Calculator is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Computes the Jacobs 1990 Risk of Malignancy Index (RMI = U × M × CA125) for ovarian mass evaluation and flags if RMI exceeds the 200 threshold.

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/rmi
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/jacobs-1990-risk-of-malignancy-index-rmi-calculator-fc43df41
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5CTTs5zXogsKodCN0vY9t

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 jacobs-1990-risk-of-malignancy-index-rmi-calculator-fc43df41
```

Example prompt: Calculate the Jacobs 1990 RMI for a postmenopausal patient with a CA125 of 85 U/ml and an ultrasound score of 3 — tell me the RMI value and whether it exceeds 200.

## When to prefer this

Use this endpoint when you need a fast, standards-compliant implementation of the original Jacobs 1990 RMI formula specifically. Prefer it over manual calculation to avoid rounding errors and ultrasound-score misassignment. Note this implements the classic RMI-1 only — not RMI-2 (Tingulstad 1996) or RMI-3 (Tingulstad 1999) — so choose accordingly when the clinical protocol specifies which version to use.

## Known failure modes

- Invalid ultrasound_score value (only 0, 1, or 3 accepted — value 2 is not valid per Jacobs 1990)
- CA125 value out of supported range (0–50000 U/ml)
- Missing required query parameters (ca125_u_ml, ultrasound_score, postmenopausal)
- Payment failure or x402 authorization error resulting in 402 response
- Non-numeric CA125 input causing schema validation error

## How this service works

Jacobs 1990 risk of malignancy index: RMI = U × M × CA125 (U/ml). Caller assigns ultrasound_score 0, 1, or 3 (never 2) and postmenopausal (M=3 if true, else 1). Returns rmi to 1 decimal and exceeds_200 (true if RMI > 200). Not an ovarian-cancer diagnosis and not later RMI-2 or RMI-3.

## Output

Returns the computed RMI value rounded to one decimal place (RMI = ultrasound_score × menopausal_multiplier × CA125) and a boolean field exceeds_200 indicating whether the RMI surpasses the clinically significant 200 threshold.

## 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": [
      "ca125_u_ml",
      "ultrasound_score",
      "postmenopausal"
     ],
     "properties": {
      "ca125_u_ml": {
       "type": "number",
       "description": "Serum CA125 in U/ml (0-50000). Enters the product unrounded. Jacobs 1990 uses U/ml. magent does not assay CA125."
      },
      "postmenopausal": {
       "type": "boolean",
       "description": "true if postmenopausal (M=3), false if premenopausal (M=1). Jacobs 1990: more than one year since final period, or age >50 after hysterectomy. Caller sets the flag; magent does not date menses."
      },
      "ultrasound_score": {
       "enum": [
        0,
        1,
        3
       ],
       "type": "integer",
       "description": "Caller-assigned Jacobs 1990 ultrasound score: 0 if no features, 1 if one feature, 3 if two or more of multilocular cyst, solid areas, bilateral lesions, ascites, or intra-abdominal metastases. Never 2. magent does not read ultrasound."
      }
     }
    }
   },
   "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/jacobs-1990-risk-of-malignancy-index-rmi-calculator-fc43df41/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)