WHO Oral Mucositis Grade
The WHO oral toxicity scale (WHO Handbook for Reporting Results of Cancer Treatment, 1979) grades oral mucositis 0 to 4: grade 0 = No mucositis.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Mucosal appearance
- Erythema and ulcers
- What the patient can tolerate
- Able to tolerate solids
Result: 2
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Grade 0
- No mucositis.
- Grade 1
- Soreness or erythema only - no ulcers.
- Grade 2
- Erythema and ulcers, able to tolerate solids.
- Grade 3
- Unable to tolerate solids but able to tolerate liquids.
- Grade 4
- Unable to tolerate solids or liquids. Oral alimentation is not possible.
- Above 2
- THE APPEARANCE STOPS MATTERING. Grades 3 and 4 are separated purely by diet, whatever the mucosa looks like.
- Extent
- Extensive ulceration does NOT raise the grade past 2 if solids are tolerated. The extent of ulceration is not scored at all - only its presence.
- Not anatomic
- A mouth that looks far worse can carry the same grade, and one that looks better can carry a higher grade. This is not an anatomic severity measure.
- Attribution
- The definitions say what the patient can tolerate, NOT WHY. A high grade does not establish that the mucosa is the cause.
- Purpose
- Built for REPORTING - the 1979 WHO handbook - to standardize reporting of cancer-treatment complications, so its purpose is trial comparability.
- Scope
- Does not diagnose mucositis or its cause, does not measure pain, and decides no analgesia, oral care, feeding route or cancer-treatment change.
What you enter
- Mucosal appearance.
- What the patient can tolerate.
Full field descriptions
- Mucosal appearance [normal = Normal mucosa - no mucositis; soreness-erythema = Soreness or erythema only, without ulcers; ulcers = Erythema and ulcers]. This decides grades 0 to 2 ONLY - it is ignored at grades 3 and 4.
- What the patient can tolerate [solids = Able to tolerate solids; liquids-only = Unable to tolerate solids, able to tolerate liquids; none = Unable to tolerate solids or liquids - oral alimentation is not possible]. Anything below solids sets the grade on its own.
How this is calculated
- Structure
- TWO AXES IN ONE GRADE: 0 to 2 come from the mucosal APPEARANCE, 2 to 4 come from what the patient CAN EAT. Grade 2 is the hinge.
World Health Organization. WHO Handbook for Reporting Results of Cancer Treatment. Geneva: World Health Organization; 1979. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.