ABSTRACT
There are many investigations that test for abnormalities of gastrointestinal structure and/or function. The availability of such tests is largely determined by locally agreed guidelines. These in turn depend on the local prevalence of an illness, the cost, and the expertise available to perform the investigation. Gastrointestinal investigations can be divided into the following categories: endoscopic investigations; imaging tests; liver biopsy; Helicobacter pylori testing; motility studies; manometry; pH studies; and absorption tests.
