anorectal gradient (or defecation index) in one of two ways. The anorectal gradient is either calculated as a difference (rectal pressure - anal pressure) or as a ratio (rectal pressure / anal pressure). A positive difference or a ratio over 1 indicates normal findings. Abnormal findings on manometry does not definitively indicate illness as a significant number of healthy individuals have been found to have abnormal results. Values recorded during a defecation trial are influenced by a number of factors including the degree of patient involvement in defecation efforts. Rectoanal Inhibitory Reflex (RAIR) In healthy individuals, in the process of defecating, the internal anal sphincter will reflexively relax. The lack of a rectoanal inhibitory reflex may indicate either the absence or the non-functionality of certain muscle or nerve structures involved in proper defecation. Sensation Patients are assessed on their anorectal sensory perception via the inflation of a balloon. As the balloon is inflated, its volume is recorded at certain milestones: initial sensation of the equipment, start of the sensory urge to defecate and the point of maximum discomfort. An increased level of sensation has been noted in disorders such as fecal incontinence, while a decreased level of sensation has been seen in individuals with dyssynergic defecation. Interpretation As part of the 2020 IAPWG consensus manuscript, the group published the newly created London Classification for Disorders of Anorectal Function which aimed to standardize the interpretation of anorectal manometry findings. The London Classification divided disorders into 4 parts: Under each part, there are a list of diagnosis that are made based on manometry findings. For example, under part 2 (Disorders of anal tone and contractility), listed manometric diagnoses include: anal hypotension, anal hypertension, anal hypercontractility and combined anal hypertension and hypercontractility. Findings are also divided into: major findings, minor findings and inconclusive findings. Major findings are findings that are not present in healthy patient such as rectoanal areflexia, Minor findings are findings that are more commonly found in patients with anorectal disease compared to healthy patients, while inconclusive findings are findings that may be present in both groups. Limitations Centers rely on published data sets from healthy volunteers to evaluate test findings. However, the lack of standardization in equipment usage and procedural protocol, can in certain cases, impact the ability to determine what may be considered normal or abnormal values. This is further complicated by the limited amount of data on the