Comparative Rome IV, ICD-11 and DSM-5 definitions of rumination syndrome20–22
| Rome IV | ICD-11 | DSM-5 | |
| Description | Regurgitation is followed by chewing and re-swallowing food or spitting it out No preceding retching Supportive criteria No nausea prior to regurgitation Regurgitant contains recognisable food which may be pleasant tasting Regurgitation ceases when regurgitant becomes acidic | Intentional and repeated regurgitation of ingested food This may be spat out or chewed and re-swallowed | Repeated regurgitation of food which may be re-swallowed or spat out of the mouth |
| Frequency of symptoms | – | Several times per week | – |
| Duration of symptoms | ≥3 months prior to diagnosis with initial occurrence of symptoms ≥6 months prior to diagnosis | Several weeks | ≥1 month |
DSM-5, Diagnostic and Statistical Manual for mental Disorders; ICD-11, International Classification of Diseases.