Abstract 

Background 
Acute appendicitis is one of the most prevalent causative factors of acute abdominal pain leading to emergency surgery throughout the world. Despite the improvements in diagnostic imaging and laboratory investigations, the correct diagnosis of acute appendicitis is still difficult, especially in emergency situations with scarce resources. Delayed diagnosis may result in serious complications including appendicle perforation, generalized peritonitis, intra-abdominal abscess formation, as well as increased morbidity in the postoperative period including surgical site infections. On the other hand, unnecessary appendectomy because of over diagnosis exposes patients to avoidable risks of surgery and higher health care cost. In order to conduct an accurate diagnosis and avoid the negative appendectomy rate, some clinical scoring systems have been proposed, and among them the Alvarado score and the RIPASA are commonly used.

Objective  
To compare the diagnostic accuracy of Alvarado and RIPASA scoring system among patients with a suspected diagnosis of acute appendicitis. 

Methodology 
This is a comparative observational study which was carried out in the Department of General Surgery at Lady Reading Hospital, Peshawar for a time period of one year from August 2024 to August 2025. Patients between 15-60 years of age with right lower quadrant abdominal pain accompanied by clinical suspicion of acute appendicitis were included. Each patient was assessed using both the Alvarado and RIPASA scoring systems before surgical intervention. All patients had undergone appendectomy and histopathological examination of the resected appendix was considered the gold standard for the diagnosis. Diagnostic performance parameters such as sensitivity, specificity, positive and negative predictive value and overall diagnostic accuracy were evaluated for both the scoring systems. 

Results 
The RIPASA score showed its superiority in the diagnosis of acute appendicitis with higher sensitivity and overall diagnostic accuracy in comparison to the Alvarado score. Comparatively high specificity and low sensitivity were reported in the Alvarado score. Overall, the RIPASA scoring system proved more useful in detecting the true case of acute appendicitis and hence its superiority as a diagnostic tool in the studied population. 

 Keywords
Acute appendicitis; RIPASA score; Alvarado score; diagnostic accuracy; sensitivity; specificity