A study carried out by the HRB Centre for Primary Care Research, based in the Royal College of Surgeons in Ireland (RCSI), has completed a systematic review of 42 validation studies of the Alvarado score, a clinical prediction rule which is used for predicting the likelihood of appendicitis in patients presenting with abdominal pain.

The main analysis focused on three subgroups of patients; men, woman and children as age and gender can affect the performance of the rule. The study found the score performed well in men, but it was inconsistent in children and over-predicted the probability of appendicitis in women.

Commenting on the review, Professor Tom Fahey, Principal Investigator at the HRB Centre, said: "The diagnosis of appendicitis, particularly at an early stage of presentation in GP or primary care settings can be a challenge, as the signs and symptoms overlap with a number of other conditions. Our review found that the Alvarado score is useful for ruling out appendicitis and can be used to predict which patients are low risk and can therefore be safely discharged. However, the score performed less well at ruling in appendicitis and it is not recommended as the sole criteria for proceeding with surgery."

The Alvarado score is a 10 point scoring system which uses clinical signs, symptoms and diagnostic tests to predict the likelihood of appendicitis. The score is also known by the acronym MANTRELS, with one point scored for the presence of ‘migration of pain', ‘anorexia', ‘nausea', ‘rebound pain', ‘elevated temperature' or ‘shift of white blood count to the left' and two points scored for ‘tenderness in right lower quadrant' and leucocytosis'. Based on the total score, the Alvarado score enables risk stratification, linking the probability of appendicitis to recommendations regarding discharge, observation or surgical intervention.

The score may be of particular interest for use in low resource settings where imaging is not an option or may be useful as a triage tool to decide which patients should receive imaging.

The paper, ‘The Alvarado score for predicting acute appendicitis: a systematic review' was published in the open accessed journal, BMC Medicine.

The research was conducted by two RCSI medical students Dr Robert Ohle and Dr Fran O'Reilly in the HRB Centre for Primary Care Research, supervised by members of the Centre. The HRB Centre is a five-year programme funded by the Health Research Board (HRB).