> ## Documentation Index
> Fetch the complete documentation index at: https://docs.medera.info/llms.txt
> Use this file to discover all available pages before exploring further.

# ICD-10-CM

> US diagnosis coding — full F-code coverage.

ICD-10-CM is the US standard for diagnosis coding. Maintained by NCHS + CMS, updated annually on October 1. Medera covers the full ICD-10-CM surface with **calibration on the F-code (mental, behavioral, and neurodevelopmental disorders) chapter**.

## F-code chapter coverage

| Range         | Domain                                                            |
| :------------ | :---------------------------------------------------------------- |
| `F01` – `F09` | Mental disorders due to known physiological conditions            |
| `F10` – `F19` | Mental and behavioral disorders due to psychoactive substance use |
| `F20` – `F29` | Schizophrenia spectrum                                            |
| `F30` – `F39` | Mood (affective) disorders                                        |
| `F40` – `F48` | Anxiety, dissociative, stress-related disorders                   |
| `F50` – `F59` | Behavioral syndromes (eating, sleep)                              |
| `F60` – `F69` | Personality disorders                                             |
| `F70` – `F79` | Intellectual disabilities                                         |
| `F80` – `F89` | Pervasive and specific developmental disorders                    |
| `F90` – `F98` | Behavioral disorders with onset in childhood                      |
| `F99`         | Unspecified mental disorder                                       |

## Specificity expansion

The Medera engine surfaces specificity gaps as `severity_qualifier_suggestions`. Example:

```json theme={"system"}
{
  "code": "F32.0",
  "display": "MDD single episode, mild",
  "severity_qualifier_suggestions": ["F32.1 (moderate)", "F32.2 (severe without psychotic)"],
  "documentation_gap": "Severity qualifier (mild / moderate / severe) not explicitly documented"
}
```

## Pair with CPT

For US outpatient BH encounters, pair ICD-10-CM with CPT 9079x (eval) / 9083x (psychotherapy) / 9921x (E/M). See [Coding Systems](/coding/coding-systems) for recommended pairings.

***

## What's next

<CardGroup cols={2}>
  <Card title="CPT" icon="https://mintcdn.com/medera-357fd587/iC-6rAuwl-0aQSw_/icons/ui/hashtag.svg?fit=max&auto=format&n=iC-6rAuwl-0aQSw_&q=85&s=aad176642277709c5c2964dfa5bea30d" href="/coding/cpt" width="40" height="40" data-path="icons/ui/hashtag.svg">Procedure + E/M.</Card>
  <Card title="HCPCS Level II" icon="https://mintcdn.com/medera-357fd587/iC-6rAuwl-0aQSw_/icons/ui/hashtag.svg?fit=max&auto=format&n=iC-6rAuwl-0aQSw_&q=85&s=aad176642277709c5c2964dfa5bea30d" href="/coding/hcpcs" width="40" height="40" data-path="icons/ui/hashtag.svg">BH-specific H- and S-codes.</Card>
  <Card title="CDI" icon="https://mintcdn.com/medera-357fd587/iC-6rAuwl-0aQSw_/icons/ui/file-pen.svg?fit=max&auto=format&n=iC-6rAuwl-0aQSw_&q=85&s=7a092163a19603cf99af65ed0de4639b" href="/coding/cdi" width="40" height="40" data-path="icons/ui/file-pen.svg">Documentation gaps.</Card>
  <Card title="Encounter coding" icon="https://mintcdn.com/medera-357fd587/iC-6rAuwl-0aQSw_/icons/ui/clipboard-check.svg?fit=max&auto=format&n=iC-6rAuwl-0aQSw_&q=85&s=9cf869d685b45a2ec31be2b3d675a841" href="/coding/encounter-coding" width="40" height="40" data-path="icons/ui/clipboard-check.svg">Use cases.</Card>
</CardGroup>