The purpose of this paper is to identify a list of clinical, laboratory and instrumental tools suitable to assess the presence of gastrointestinal involvement in SSc patients to be included in clinical investigational studies. The pertinent literature was reviewed to select those variables which have been demonstrated to be valid, reliable and feasible. A minimal core set of variables has been identified to be used in clinical investigation for the assessment of esophagus, stomach, small intestine, colon and anorectum involvement in scleroderma patients.