The Alvarado score and acute appendicitis.

INTRODUCTION This is a retrospective study to assess the accuracy of the Alvarado score in predicting appendicitis for patients with right iliac fossa pain. MATERIALS AND METHODS This is a retrospective study of consecutive patients with suspected appendicitis. The Alvarado score was computed from the admission notes and correlated with the final outcome of the patient. Patients discharged without surgery were reviewed in the outpatient's clinic to ascertain that they did not need surgery. RESULTS There were 148 patients in the study and 63 had appendectomies with intention to treat appendicitis. The normal appendicectomy rate was 21%. The number of patients with score 1-4, 5-6, 7-8 and 9-10 were 46, 40, 44 and 18, respectively, while the number of appendicitis in each group were 0, 2 (5%), 30 (68%) and 18 (100%), respectively. The positive and negative predictive values of Alvarado's scores of 7 or more were 77% and 97.6%, respectively. CONCLUSION Alvarado score is a useful tool in the diagnosis of appendicitis, especially at both ends of the scale.