Evaluating the Diagnostic Efficacy of RIPASA vs. Alvarado Scores in Acute Appendicitis: A Prospective Comparative Analysis

Abstract

Background: Appendicitis is the third most common cause of emergency abdominal surgery worldwide, but diagnosis remains challenging. Clinical scoring systems like Alvarado and RIPASA aim to improve diagnostic accuracy. While the Alvarado score is widely accepted, it is more commonly applied in Western populations. In contrast, the RIPASA score was developed for Southeast Asian populations, reflecting demographic variations in appendicitis presentation. This study compares the accuracy of the RIPASA and Alvarado scores against histopathological findings, the traditional gold standard.

Methods: A prospective, comparative study was conducted on 255 patients with suspected acute appendicitis. Upon admission, both RIPASA and Alvarado scores were calculated. Diagnostic performance was evaluated using sensitivity, specificity, PPV, NPV, and overall accuracy. Concordance between scoring systems was analyzed with Cohen’s Kappa, and McNemar’s test assessed statistical significance in performance differences.

Results: The RIPASA score demonstrated superior sensitivity at 92% compared to 85% for Alvarado, with both scoring 75% specificity. The PPV for RIPASA was 96%, marginally higher than Alvarado’s 95%, indicating high accuracy in detecting true positives. RIPASA’s NPV was 75%, yielding fewer false negatives than Alvarado. McNemar’s test showed a significant difference (p < 0.05) favoring RIPASA, and Cohen’s Kappa indicated moderate to substantial agreement (0.6–0.8). Conclusion: RIPASA offers better diagnostic performance than Alvarado, particularly in multicultural settings, due to its higher sensitivity and comparable specificity. While both scores have moderate NPVs, additional diagnostic methods may be necessary for complex cases. Further studies are needed to validate these findings across diverse populations