Table 2. Classification of rectal prolapse by structure and anatomic involvement (Haskell, 2004).

Gradea	Clinical feature
I	Prolapse of the rectal mucosa only (usually intermittent).
II	Complete prolapse of all layers of the rectum (may be intermittent).
III	Rectal prolapse with intussusception of the large colon. These prolapses are longer and more painful, and clinical signs progress rapidly.
IV	Rectal prolapse but the anal sphincter is causing constriction of the prolapse.

^aThe classification was based on a previous study (Haskell, 2004).