RIPASA Score for Acute Appendicitis

Screens for acute appendicitis diagnosis based on symptoms and laboratory findings.

Refer to the text below the score for more information on the criteria used and its psychometric properties.

The RIPASA score is based on a study on Asian population and is intended to help clinicians with the differential diagnosis of acute appendicitis based on the most common symptoms such as pain of less than 48 hours in right iliac fossa, and laboratory findings such as raised WCC as sign of infection.

The RIPASA score ranges from 1.5 to 16 where the acute appendicitis diagnosis cut-off value is 7.5 points and was found to have 88% sensitivity and 67% specificity for diagnosis of appendicitis in Asian populations.

1Patient’s Demographic



Right iliac fossa (RIF) pain
Migration of pain to right lower quadrant (RLQ)
Nausea & vomiting
Duration of symptoms


Right iliac fossa (RIF) tenderness
Right iliac fossa (RIF) guarding
Rebound tenderness
Rovsing’s Sign
Fever (>37 °C)


Raised WCC
Negative urinalysis

5Additional criterion

Foreign national*

*The score is mainly for screening Asian populations and in Singapore, where it was designed, foreign national criterion was found to have some predictive capacity and introduced in the score.

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About the original study

The RIPASA score was designed by Chong et al. following the 2010 study as a scoring system for diagnosing appendicitis, more sensitive in predictive ability than the Alvarado score in Middle Eastern and Asian populations.

Clinical data was collected retrospectively from a cohort of 312 patients who had undergone an emergency appendicectomy.

15 parameters were generated and a score of 0.5, 1.0 or 2.0 was allocated to each:

Patient’s Demographic information: Gender and Age;

Symptoms: Right iliac fossa (RIF) pain, Migration of pain to right lower quadrant (RLQ), Anorexia, Nausea & vomiting, Duration of symptoms;

Signs: Right iliac fossa (RIF) tenderness, Right iliac fossa (RIF) guarding, Rebound tenderness, Rovsing’s Sign, Fever (>37 °C);

Investigations: Raised WCC, Negative urinalysis;

Additional criterion: Foreign national – as the score is mainly to be used for screening Asian populations and in Singapore, where it was designed, foreign national criterion was found to have some predictive capacity and introduced in the score.

The optimal cut-off threshold score from the receiver operating curve (ROC) was 7.5 with a sensitivity of 88%, a specificity of 67%, a positive predictive value of 93% and a negative predictive value of 53%. The negative appendicectomy rate was found to decrease from 16.3 to 6.9%.


Subsequent validation studies

In the validation study conducted by Butt et al. on a cohort of 267 patients (156 male, 111 female), the score was employed and diagnosis was made by routine sonography of abdomen. The following psychometric properties of the RIPASA were extracted:

■ Sensitivity: 96.7%

■ Specificity: 93.0%

■ Diagnostic accuracy: 95.1%

■ Positive predictive value: 94.8%

■ Negative predictive value was 95.54%.

In a comparison study conducted by Frountzas et al. between the RIPASA and Alvarado score, data from twelve studies was meta-analysed (total cohort of 2161 patients).

The sensitivity of RIPASA score was 94% (95% CI, 92%-95%) and the specificity was 55% (95% CI, 51%-55%). The sensitivity of Alvarado score was 69% (95% CI, 67%-71%) and the specificity was 77% (95% CI, 74%-80%).

The analysis concluded the RIPASA scoring system is more sensitive than Alvarado scoring but has lower specificity, thus needing supplementary means for accurate diagnosis. Both scores were recommended for aiding clinical gestalt in acute appendicitis presentations.



Original reference

Chong CF, Adi MI, Thien A, Suyoi A, Mackie AJ, Tin AS, Tripathi S, Jaman NH, Tan KK, Kok KY, Mathew VV, Paw O, Chua HB, Yapp SK. Development of the RIPASA score: a new appendicitis scoring system for the diagnosis of acute appendicitis. Singapore Med J. 2010; 51(3):220-5.


Butt MQ, Chatha SS, Ghumman AQ, Farooq M. RIPASA score: a new diagnostic score for diagnosis of acute appendicitis. J Coll Physicians Surg Pak. 2014; 24(12):894-7.

Other references

Chong CF, Thien A, Mackie AJ, Tin AS, Tripathi S, Ahmad MA, Tan LT, Ang SH, Telisinghe PU. Comparison of RIPASA and Alvarado scores for the diagnosis of acute appendicitis. Singapore Med J. 2011; 52(5):340-5.

Frountzas M, Stergios K, Kopsini D, Schizas D, Kontzoglou K, Toutouzas K. Alvarado or RIPASA score for diagnosis of acute appendicitis? A meta-analysis of randomized trials. Int J Surg. 2018; 56:307-314.

Specialty: Gastroenterology

System: Digestive

Objective: Screening

No. Of Criteria: 15

Abbreviation: RIPASA

Article By: Denise Nedea

Published On: April 17, 2020 · 12:00 AM

Last Checked: April 17, 2020

Next Review: April 17, 2025