| WI 100 - General Works | WI 200 - Lips. Mouth | WI 407 - Diarrhea | WI 520 - Colon |
| WI 101 - Anatomy. Histology. Embryology | WI 210 - Tongue. Taste Buds | WI 409 - Constipation | WI 528 - Megacolon |
| WI 113 - Popular Works (General) Hygiene | WI 230 - Salivary Glands | WI 412 - Congenital Malformations | WI 530 - Cecum |
| WI 140 - Diseases (General) | WI 250 - Esophagus | WI 420 - Inflammation | WI 535 - Appendix |
| WI 141 - Examination. Diagnosis. Diagnostic Methods. Monitoring (General) | WI 300 - Stomach | WI 412 - Diverticulitis | WI 560 - Rectum |
| WI 143 - Symptomatology. Manifestations of disease | WI 308 - Achlorhydria | WI 430 - Polyps. Polyposis | WI 575 - Peritoneum. Omentum. Peritoneal cavity. Retroperitoneal space |
| WI 145 - Dyspepsia and related conditions | WI 3I0 - Gastritis | WI 480 - Surgery (General) | WI 600 - Anus and Rectum |
| WI 146 - Nausea. Vomiting | WI 350 - Peptic Ulcer | WI 500 - Small Intestine. Mesentery | WI 700 - Liver and Biliary Tract |
| WI 147 - Abdominal Pain | WI 380 - Surgery. Postgastrectomy syndromes | WI 505 - Duodenum | WI 800 - Pancreas |
| WI 149 - Neoplasms | WI 387 - Pylorus. Pyloric antrum. Pyloric stenosis | WI 510 - Jejunum | WI 900 - Abdomen and Abdominal Surgery |
| WI 150 Functional Disorders | WI 400 - Intestines | WI 512 - Ileum | WI 950 - Hernia |
Classification Scheme reproduced by kind permission of the National Library of Medicine