Abstract:

Background: Acute appendicitis is a common surgical emergency, and the Alvarado Scoring System is a widely used clinical prediction tool. This study aimed to evaluate the diagnostic accuracy of the Alvarado score in patients presenting with suspected appendicitis to a tertiary care hospital serving a hilly region of Northern India.

Methods: A prospective observational study was conducted from May 2021 to April 2022 at Dr. Radhakrishnan Government Medical College, Hamirpur (HP). Eighty-four patients aged ≥12 years with clinically suspected appendicitis had Alvarado scores calculated at presentation. All patients underwent appendectomy, with histopathological examination (HPE) serving as the reference standard. Diagnostic metrics including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, likelihood ratios, and area under the receiver operating characteristic curve (AUC-ROC) were calculated at a primary cut-off of ≥7.

Results: HPE confirmed acute appendicitis in 79 of 84 patients (94.05%). At a cut-off of ≥7, the study found: true positives (TP) = 68, false positives (FP) = 2, false negatives (FN) = 11, and true negatives (TN) = 3. Calculated metrics were: sensitivity 86.08% (95% CI 76.0–92.7%), specificity 60.00% (95% CI 14.7–94.7%), PPV 97.14%, NPV 21.43%, and overall accuracy 84.52%. The AUC for the Alvarado score was 0.89, indicating good discrimination.

Conclusion: In this high-prevalence cohort from a hilly region, the Alvarado Score demonstrated good sensitivity and excellent PPV but poor NPV. The score is useful to "rule in" appendicitis when high but is insufficient to reliably "rule out" the disease when low. Clinical judgment and adjunctive imaging or biomarkers remain essential, particularly in resource-limited settings.