# Rome IV F3 functional defecation disorders

Rome IV functional defecation

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/rome_iv_functional_defecation`
HTML: https://magentlab.com/docs/rome-iv-functional-defecation
Markdown: https://magentlab.com/docs/rome-iv-functional-defecation.md

Not a medical device. Not a diagnosis, dose, or listing recommendation.

## What it computes

Apply the Rao 2016 Rome IV F3 functional defecation disorders criteria and return evacuation_tests_met (0-3) and whether the published F3 parent box holds (rome_iv_functional_defecation).

## When to use

When an agent already has the caller-assigned Rao 2016 F3 flags (FC and/or IBS with constipation already satisfied, plus the three evacuation-test results and timing) and needs whether the published F3 parent box holds. magent does not re-run FC or IBS-C and does not perform balloon expulsion, manometry, EMG, or imaging.

## When not to use

- Not a medical device.
- Not a diagnosis. magent does not diagnose functional defecation disorders.
- The caller assigns the six flags. magent does not perform balloon expulsion, anorectal manometry, anal surface EMG, or imaging, and does not re-run functional constipation or IBS with constipation.
- This tool is the Rao 2016 Rome IV F3 parent box only. F3a inadequate propulsion and F3b dyssynergic defecation apply to patients who already satisfy FDD and are copy-only; they are not separate diagnoses from this tool.

## Formula

```
rome_iv_functional_defecation iff satisfies_fc_and_or_ibs_with_constipation and evacuation_tests_met >= 2 and fulfilled_last_3_months and onset_at_least_6_months; evacuation_tests_met counts abnormal_balloon_expulsion, abnormal_anorectal_evacuation_pattern_manometry_or_emg, and impaired_rectal_evacuation_by_imaging (Rao 2016 Rome IV F3 functional defecation disorders)
```

## Citation

[Anorectal Disorders](https://doi.org/10.1053/j.gastro.2016.02.009)
Rao SSC, Bharucha AE, Chiarioni G, Felt-Bersma R, Knowles C, Malcolm A, Wald A
Gastroenterology. 2016;150(6):1430-1442
DOI: [10.1053/j.gastro.2016.02.009](https://doi.org/10.1053/j.gastro.2016.02.009)

## Worked example

### FC or IBS-C, two of three evacuation tests, and timing

Given: `abnormal_anorectal_evacuation_pattern_manometry_or_emg=true, abnormal_balloon_expulsion=true, fulfilled_last_3_months=true, impaired_rectal_evacuation_by_imaging=false, onset_at_least_6_months=true, satisfies_fc_and_or_ibs_with_constipation=true`

1. Functional constipation and/or IBS with constipation is true
2. Abnormal balloon expulsion and abnormal anorectal evacuation pattern with manometry or EMG are true; impaired rectal evacuation by imaging is false (2 of 3)
3. Criteria fulfilled for the last 3 months and onset at least 6 months prior are true
4. rome_iv_functional_defecation is true


### FC or IBS-C and timing with only one evacuation test

Given: `abnormal_anorectal_evacuation_pattern_manometry_or_emg=false, abnormal_balloon_expulsion=true, fulfilled_last_3_months=true, impaired_rectal_evacuation_by_imaging=false, onset_at_least_6_months=true, satisfies_fc_and_or_ibs_with_constipation=true`

1. Functional constipation and/or IBS with constipation and timing hold
2. Only abnormal balloon expulsion is true (1 of 3)
3. rome_iv_functional_defecation is false


## Also searched as

- Rome IV functional defecation
- Rome IV F3
- Rao 2016 F3
- functional defecation disorders
- Rome IV FDD
- balloon expulsion Rome IV
- anorectal manometry EMG Rome IV
- Rao 2016 anorectal disorders
- impaired rectal evacuation

## Parameters

- `satisfies_fc_and_or_ibs_with_constipation` (boolean, required): The patient already satisfies diagnostic criteria for functional constipation and/or IBS with constipation, as assigned (Rao 2016 F3). true or false as assigned by the caller. magent does not re-run those tools.
- `abnormal_balloon_expulsion` (boolean, required): Abnormal balloon expulsion test (one of three evacuation tests; at least two required). true or false as assigned by the caller. magent does not perform balloon expulsion.
- `abnormal_anorectal_evacuation_pattern_manometry_or_emg` (boolean, required): Abnormal anorectal evacuation pattern with manometry or anal surface EMG (one of three evacuation tests; at least two required). true or false as assigned by the caller. magent does not perform manometry or EMG.
- `impaired_rectal_evacuation_by_imaging` (boolean, required): Impaired rectal evacuation by imaging (one of three evacuation tests; at least two required). true or false as assigned by the caller. magent does not perform imaging.
- `fulfilled_last_3_months` (boolean, required): Criteria fulfilled for the last 3 months, as assigned (Rao 2016). true or false as assigned by the caller. magent does not take a history.
- `onset_at_least_6_months` (boolean, required): Symptom onset at least 6 months prior to diagnosis, as assigned (Rao 2016). true or false as assigned by the caller. magent does not take a history.

## Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

Method: `POST /api/calc/rome_iv_functional_defecation`
Max items: 25
Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic)
Status: PREVIEW

- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
- The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
- HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
- Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
- x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request:

```json
{
  "items": [
    {
      "abnormal_anorectal_evacuation_pattern_manometry_or_emg": "true",
      "abnormal_balloon_expulsion": "true",
      "fulfilled_last_3_months": "true",
      "impaired_rectal_evacuation_by_imaging": "false",
      "onset_at_least_6_months": "true",
      "satisfies_fc_and_or_ibs_with_constipation": "true"
    },
    {
      "abnormal_anorectal_evacuation_pattern_manometry_or_emg": "true",
      "abnormal_balloon_expulsion": "true",
      "fulfilled_last_3_months": "true",
      "impaired_rectal_evacuation_by_imaging": "false",
      "onset_at_least_6_months": "true",
      "satisfies_fc_and_or_ibs_with_constipation": "true"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/rome-iv-functional-defecation

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/rome_iv_functional_defecation",
  "items": [
    {
      "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.",
      "citation": {
        "authors": "Rao SSC, Bharucha AE, Chiarioni G, Felt-Bersma R, Knowles C, Malcolm A, Wald A",
        "doi": "10.1053/j.gastro.2016.02.009",
        "id": "rao-2016",
        "pmid": "27144630",
        "source": "Gastroenterology. 2016;150(6):1430-1442",
        "title": "Anorectal Disorders"
      },
      "formula": "rome_iv_functional_defecation",
      "formula_expression": "rome_iv_functional_defecation iff satisfies_fc_and_or_ibs_with_constipation and evacuation_tests_met >= 2 and fulfilled_last_3_months and onset_at_least_6_months; evacuation_tests_met counts abnormal_balloon_expulsion, abnormal_anorectal_evacuation_pattern_manometry_or_emg, and impaired_rectal_evacuation_by_imaging (Rao 2016 Rome IV F3 functional defecation disorders)",
      "criteria": [
        {
          "factor": "satisfies_fc_and_or_ibs_with_constipation",
          "met": true
        },
        {
          "factor": "abnormal_balloon_expulsion",
          "met": true
        },
        {
          "factor": "abnormal_anorectal_evacuation_pattern_manometry_or_emg",
          "met": true
        },
        {
          "factor": "impaired_rectal_evacuation_by_imaging",
          "met": false
        },
        {
          "factor": "fulfilled_last_3_months",
          "met": true
        },
        {
          "factor": "onset_at_least_6_months",
          "met": true
        },
        {
          "value": 2,
          "factor": "evacuation_tests_ge_2",
          "met": true
        }
      ],
      "evacuation_tests_met": 2,
      "rome_iv_functional_defecation": true
    },
    {
      "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.",
      "citation": {
        "authors": "Rao SSC, Bharucha AE, Chiarioni G, Felt-Bersma R, Knowles C, Malcolm A, Wald A",
        "doi": "10.1053/j.gastro.2016.02.009",
        "id": "rao-2016",
        "pmid": "27144630",
        "source": "Gastroenterology. 2016;150(6):1430-1442",
        "title": "Anorectal Disorders"
      },
      "formula": "rome_iv_functional_defecation",
      "formula_expression": "rome_iv_functional_defecation iff satisfies_fc_and_or_ibs_with_constipation and evacuation_tests_met >= 2 and fulfilled_last_3_months and onset_at_least_6_months; evacuation_tests_met counts abnormal_balloon_expulsion, abnormal_anorectal_evacuation_pattern_manometry_or_emg, and impaired_rectal_evacuation_by_imaging (Rao 2016 Rome IV F3 functional defecation disorders)",
      "criteria": [
        {
          "factor": "satisfies_fc_and_or_ibs_with_constipation",
          "met": true
        },
        {
          "factor": "abnormal_balloon_expulsion",
          "met": true
        },
        {
          "factor": "abnormal_anorectal_evacuation_pattern_manometry_or_emg",
          "met": true
        },
        {
          "factor": "impaired_rectal_evacuation_by_imaging",
          "met": false
        },
        {
          "factor": "fulfilled_last_3_months",
          "met": true
        },
        {
          "factor": "onset_at_least_6_months",
          "met": true
        },
        {
          "value": 2,
          "factor": "evacuation_tests_ge_2",
          "met": true
        }
      ],
      "evacuation_tests_met": 2,
      "rome_iv_functional_defecation": true
    }
  ]
}
```

## Response fields

- `formula` (string): rome_iv_functional_defecation
- `formula_expression` (string): Rao 2016 Rome IV F3: FC and/or IBS-C, at least 2 of 3 evacuation tests, last-3-months criteria, and 6-month onset
- `evacuation_tests_met` (integer): Count of true evacuation tests among abnormal balloon expulsion, abnormal anorectal evacuation pattern with manometry or anal surface EMG, and impaired rectal evacuation by imaging (0-3)
- `rome_iv_functional_defecation` (boolean): true only when FC and/or IBS-C, at least two evacuation tests, last-3-months criteria, and 6-month onset all hold. Not a diagnosis.
- `criteria` (array): Per-factor rows with factor and met; evacuation_tests_ge_2 includes value 0-3
- `citation` (object): Rao 2016 Gastroenterology citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "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.",
  "citation": {
    "authors": "Rao SSC, Bharucha AE, Chiarioni G, Felt-Bersma R, Knowles C, Malcolm A, Wald A",
    "doi": "10.1053/j.gastro.2016.02.009",
    "id": "rao-2016",
    "pmid": "27144630",
    "source": "Gastroenterology. 2016;150(6):1430-1442",
    "title": "Anorectal Disorders"
  },
  "formula": "rome_iv_functional_defecation",
  "formula_expression": "rome_iv_functional_defecation iff satisfies_fc_and_or_ibs_with_constipation and evacuation_tests_met >= 2 and fulfilled_last_3_months and onset_at_least_6_months; evacuation_tests_met counts abnormal_balloon_expulsion, abnormal_anorectal_evacuation_pattern_manometry_or_emg, and impaired_rectal_evacuation_by_imaging (Rao 2016 Rome IV F3 functional defecation disorders)",
  "criteria": [
    {
      "factor": "satisfies_fc_and_or_ibs_with_constipation",
      "met": true
    },
    {
      "factor": "abnormal_balloon_expulsion",
      "met": true
    },
    {
      "factor": "abnormal_anorectal_evacuation_pattern_manometry_or_emg",
      "met": true
    },
    {
      "factor": "impaired_rectal_evacuation_by_imaging",
      "met": false
    },
    {
      "factor": "fulfilled_last_3_months",
      "met": true
    },
    {
      "factor": "onset_at_least_6_months",
      "met": true
    },
    {
      "value": 2,
      "factor": "evacuation_tests_ge_2",
      "met": true
    }
  ],
  "evacuation_tests_met": 2,
  "rome_iv_functional_defecation": true
}
```

## Errors

- HTTP 400 `invalid_rome_iv_functional_defecation`: Rome IV functional defecation needs the Rao 2016 F3 constipation and evacuation-test flags. Returned before settlement; you are not charged.
- HTTP 400 `invalid_flag`: boolean clinical flags must be true or false Returned before settlement; you are not charged.
- HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
- HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
- HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged.

Shared HTTP 402 and 503: https://magentlab.com/docs/payments

## Related tools

- [Rome IV FC](https://magentlab.com/docs/rome-iv-fc) — Apply the Mearin 2016 Rome IV C2 functional constipation criteria and return symptom_count (0-6) and whether the published C2 box holds (rome_iv_fc).
- [Rome IV IBS](https://magentlab.com/docs/rome-iv-ibs) — Apply the Mearin 2016 Rome IV IBS diagnostic criteria and return supporting_features_met (0-3) and whether the published IBS box holds (rome_iv_ibs).

## Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional.
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.
- offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers).

Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments

Stdio MCP (one process per host): https://magentlab.com/docs/mcp

## Guarantees

- HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
- exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
- HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.