evaluation of the modified alvarado score

various scoring systems have been devised to aid diagnosis of acute appendicitis. the main objective of this study was finding the accuracy of modified alvarado score in prediction of acute appendicitis. the registries of cases with appendectomy, who had been admitted to a referral medical center in the capital of iran from february 2000 to march 2004, were studied. sensitivity and specificity of modified alvarado scoring and clinical diagnostic system used in our center were calculated. roc curve analysis demonstrated increasing chance of acute appendicitis by increasing of the modified alvarado score ( p = 0.001), but it was neither sensitive nor specific (sensitivity, 55%; specificity, 59%). diagnosis based on surgeons' decision was more sensitive than alvarado scoring (sensitivity 93-95% in different age groups). diagnosis of acute appendicitis based on surgeons' decision is more helpful than modified alvarado score.