Introduction For patients presenting to the Emergency room or OPD with acute severe right iliac fossa pain, the clinicians mostly prefer acute appendicitis as the first diagnosis, though many other differential diagnoses are there. Usually, in ER or OPD, clinical scores such as Alvarado Score, Ripasa scoring, and Tzanakis Scoring to diagnose Acute appendicitis. All these scores have different overlapping parameters and variable amounts of weightage. It is important to understand how sensitive and specific these scores are to determine the most accurate score to accurately diagnose acute appendicitis. Objectives Determine the Diagnostic accuracy of Alvarado Scoring, Ripasa Scoring, and Tzanakis Scoring compared to the Gold Standard Histopathology report. Methodology A Retrospective observational design was formulated where data of patients coming to the ER and OPD of the affiliated tertiary care hospital with right iliac fossa pain were enrolled. From the data, all clinical scores were calculated as per the standard guideline and the results of the scores were correlated with the gold standard Intraoperative Surgeon's opinion and the patient's histopathological report to determine the sensitivity, specificity, Youden Index and Accuracy of all the scores. Statistical software like EXCEL and SPSS along with Medcalc was used to produce the ROC Curve (Receiver Operating Characteristic Curve) & AUC of ROC and Fagan's Nomogram. Results:- A total of 237 patients were enrolled who presented with right iliac fossa pain of which 156 were confirmed from the Histopathology report as patients with Acute Appendicitis. The Sensitivity was calculated for Alvarado (0.487), Ripasa (0.641), and Tzanakis(0.8269) whereas the Calculated Specificity was for Alvarado(0.8148), Ripasa(0.8395), Tzanakis(0.9699). The Younden Index was highest for Tzanakis score at 0.7968. Conclusion:- The Tzanakis Score is the most accurate Scoring method to diagnose Acute Appendicitis in patients presenting with RIF pain as it includes Ultrasonography. When USG is not available, the Ripasa score is the best scoring method while we do not recommend the use of Alvarado scoring due to poor sensitivity. Key Words:- Right Iliac fossa pain, Acute Appendicitis, Alvarado, Ripasa, Tzanakis, Diagnostic test accuracy

The authors have declared no competing interest.

This study did not receive any funding

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IRB of Shrimati Nathiba Hargovandas Lakhmichand Municipal Medical College gave ethical approval for this work.

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