Comparison between diagnostic accuracy of RIPASA score and Alvarado score in the diagnosis of acute appendicitis

Background
Acute appendicitis is the most common surgical condition presented in emergency departments worldwide. It is also the most common cause of abdominal pain requiring surgery, with a lifetime risk of 7%.
Objectives
The aim of this study was to compare between the diagnostic accuracy of RIPASA score and Alvarado score in the diagnosis of acute appendicitis.
Patients and methods
This randomized prospective study was carried out on 100 patients complaining of acute abdominal pain diagnosed as appendicitis undergoing open or laparoscopic appendectomy operation in the general surgery department of Mataria Teaching Hospital, from February 2020 to August 2020. Clinical examination and laboratory workup were done to the population of the study according to the scoring systems (Alvarado and RIPASA scoring systems). Scoring was documented to every patient in the study preoperatively. The decision to operate was made by the senior surgeon (consultant), based on clinical and laboratory findings not depending on the results of the scoring systems. All patients received information about the surgical technique and risks of the operation and other options for treatment. All patients participated in this study after providing informed consent and the study was approved by the ethical committee of Ain Shams University.
Results
In our study, we found that RIPASA score was more sensitive (100 vs. 95%, respectively), and Alvarado score was more specific (38 vs. 0%, respectively). The positive predictive value for Alvarado score is significantly higher than that of RIPASA score (89 vs. 84%, respectively). The negative predictive value for Alvarado score is significantly higher than that of RIPASA score (60 vs. 0%, respectively). In our study, by using receiver operating characteristic, the area under the curve of Alvarado score is 0.924, which is greater than that for RIPASA scoring, which is 0.918. The difference in the area under the curves of 0.6% is significant between two scoring systems. The value for these two variables in both the scores is less than 0.001, which shows that there is significant association between these values. Previous studies by Arroyo-Rangel and colleagues and Pasumarthi and Madhu found that the area under the curve of RIPASA score is greater than that for Alvarado score with value less than 0.001 also.
Conclusion
Alvarado score was more specific and RIPASA scores were more sensitive. Alvarado score is shown to have a better diagnostic accuracy than RIPASA score. More trials with more number of patients should be conducted to reach an ideal score in the diagnosis of acute appendicitis.