# Maxwell 2008 Nottingham Hip Fracture Score (NHFS) Calculator

> Maxwell 2008 Nottingham Hip Fracture Score (NHFS) 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 integer Nottingham Hip Fracture Score (Maxwell 2008) from patient age, sex, hemoglobin, and four caller-assigned clinical flags, returning a score of 0–10.

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/nhfs
- 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/maxwell-2008-nottingham-hip-fracture-score-nhfs-calculator-ca96fbd7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YMkNu4QiwvDa-FssD_1eI

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 maxwell-2008-nottingham-hip-fracture-score-nhfs-calculator-ca96fbd7
```

Example prompt: Calculate the Nottingham Hip Fracture Score for a 78-year-old male patient with hemoglobin of 9.5 g/dL, AMTS ≤6, living in a nursing home, with two or more comorbidities, and no active malignancy.

## When to prefer this

Use this endpoint when you need the original Maxwell 2008 NHFS integer score for hip fracture patients — specifically when the scoring rubric must match the 2008 publication (not the 2012 or 2015 recalibrations). Ideal for clinical decision support agents that have already assessed AMTS and comorbidity counts externally, as this endpoint does not administer AMTS or enumerate comorbidities itself.

## Known failure modes

- Missing required parameters (age, sex, amts_le_6, lives_in_institution, comorbidities_ge_2, malignancy) returns a 400 error
- Providing both hemoglobin_g_l and hemoglobin_g_dl simultaneously is rejected
- Age outside 18–120 or hemoglobin outside valid range returns a validation error
- Payment failure or missing x402 payment header returns 402 Payment Required
- Invalid enum value for sex (not 'male' or 'female') causes a 400 error

## How this service works

Maxwell 2008 Nottingham hip fracture score: age <=65 0, 66-85 3, >=86 4; male 1; hemoglobin <=10 g/dL 1 (g/L / 10); caller-assigned AMTS <=6, lives in institution, >=2 comorbidities, and malignancy 1 each. Max 10. Integer score only; no predicted 30-day mortality percent. magent does not administer AMTS or clear a patient for surgery. Not the 2012 or 2015 recalibrations.

## Output

Returns a single integer NHFS score from 0 to 10 based on the Maxwell 2008 criteria. No predicted 30-day mortality percentage is returned. Age contributes 0 (≤65), 3 (66–85), or 4 (≥86); male sex adds 1; hemoglobin ≤10 g/dL adds 1; each of AMTS ≤6, institutional residence, ≥2 comorbidities, and active malignancy adds 1 point.

## 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": [
      "age",
      "sex",
      "amts_le_6",
      "lives_in_institution",
      "comorbidities_ge_2",
      "malignancy"
     ],
     "properties": {
      "age": {
       "type": "integer",
       "description": "Age in years (18-120). ≤65 scores 0; 66-85 scores 3; ≥86 scores 4 (Maxwell 2008)."
      },
      "sex": {
       "enum": [
        "female",
        "male"
       ],
       "type": "string",
       "description": "female or male. Male scores 1; female scores 0."
      },
      "amts_le_6": {
       "type": "boolean",
       "description": "Abbreviated Mental Test Score ≤6/10 as assigned by the caller (Maxwell 2008). true or false. magent does not administer AMTS. 1 point if true."
      },
      "malignancy": {
       "type": "boolean",
       "description": "Active malignancy (Maxwell 2008: within 20 years) as assigned by the caller. true or false. magent does not take a cancer history. 1 point if true."
      },
      "hemoglobin_g_l": {
       "type": "number",
       "description": "Hemoglobin in g/L (30-220). Converted as hemoglobin_g_dl = hemoglobin_g_l / 10. Provide this or hemoglobin_g_dl, not both."
      },
      "hemoglobin_g_dl": {
       "type": "number",
       "description": "Hemoglobin in g/dL (3-22). Provide this or hemoglobin_g_l, not both. ≤10 g/dL scores 1 (10.0 scores; 10.1 does not)."
      },
      "comorbidities_ge_2": {
       "type": "boolean",
       "description": "Two or more comorbidities as defined in Maxwell 2008, as assigned by the caller. true or false. magent does not enumerate comorbidities. 1 point if true."
      },
      "lives_in_institution": {
       "type": "boolean",
       "description": "Lives in an institution as assigned by the caller (Maxwell 2008). true or false. 1 point if true."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/maxwell-2008-nottingham-hip-fracture-score-nhfs-calculator-ca96fbd7/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)