Definition of Screening Status in Case-Control Studies of the Efficacy of Endoscopy

Our study does not deal with screening, and we have been careful to avoid this term when referring to our data. In contradistinction to what Weiss writes in his letter, our study compared case and control subjects with respect to the number of endoscopic procedures, irrespective of their particular indication. In many clinical situations, the distinction between screening and diagnostic procedures becomes rather artificial. As health insurance or hospital policy may not support screening tests, such procedures are justified by attaching to them unspecific diagnoses, such as abdominal pain, changes in bowel habits, or suspicion of hemorrhage in the gastrointestinal tract. A digital rectal examination and a subsequent Hemoccult test are considered by many physicians to be an integral part of the regular physical examination. The high rate of false-positive Hemoccult test results leads to many subsequent radiographic and endoscopic examinations for workup of suspected malignancy. Although such examinations may