F54 — Psychological and behavioural factors associated with disorders or diseases classified elsewhere

Concept, in one sentence

F54 is an additional code, used alongside a diagnosed physical disease's own code, for psychological/behavioural factors clearly and adversely affecting that disease's course or management.

Decisive boundary cues

• An actual diagnosed physical disease, plus a documented link to psychological/behavioural factors affecting it -> weighs toward F54.
• An unexplained physical symptom with no diagnosed disease -> weighs toward F45 instead.
• A primary postpartum mental disturbance with no separate diagnosed physical disease -> weighs toward F53 instead.

Duration/course cue

Not duration-based; defined by a documented adverse link to an already-diagnosed disease's course.

Nearest alternatives

f45, f53

Common mistake

Applying F54 to an unexplained physical symptom with no actual diagnosed disease to attach it to.

Retrieval prompt — one-line memory anchor

Is there an actual, already-diagnosed physical disease, and is there documented evidence that psychological/behavioural factors are affecting its course?