Alvarado score: an admission criterion in patients with right iliac fossa pain.

Appendicitis is an important differential diagnosis in patients with right iliac fossa pain. The diagnosis in patients with equivocal signs can be difficult. Many patients with suspected appendicitis are admitted for observation. We studied the Alvarado scores of 175 patients who presented to the emergency department with right iliac fossa pain and found that patients with scores of 4 or less did not have appendicitis. We also present an algorithm incorporating the Alvarado score for patients with suspected appendicitis.