ICD-11 classes
21 Symptoms, signs or clinical findings, not elsewhere...
Mental or behavioural symptoms, signs or clinical findings
MB28 — Symptoms or signs related to personality features
MB28.B — Negativism

ICD-11 MB28.B — Negativism

A tendency to oppose or resist suggestions or advice, or to resist stubbornly for no apparent reason.

The diagnosis includes nothing.

The diagnosis excludes nothing.

It has no clarifying diagnoses.