Pediatric Appendicitis Score (PAS) Calculator — Samuel Score
Calculate the Pediatric Appendicitis Score (Samuel score) for children with abdominal pain — 8 signs, symptoms and blood results, 0–10 points — with low, equivocal or high risk of appendicitis.
How it works
PAS = cough/percussion/hopping tenderness 2 + right lower quadrant tenderness 2 + anorexia 1 + fever ≥ 38 °C 1 + nausea or vomiting 1 + migration of pain 1 + WBC > 10 × 10⁹/L 1 + neutrophils > 7.5 × 10⁹/L 1. Range 0–10: ≤ 3 low risk · 4–6 equivocal · ≥ 7 high risk.
The Pediatric Appendicitis Score (Samuel, Journal of Pediatric Surgery 2002) was designed for children aged 4–15 with abdominal pain. A score of 3 or less makes appendicitis unlikely, 4–6 is equivocal and usually leads to ultrasound or a period of observation, and 7 or more strongly suggests appendicitis and calls for a surgical review. Later validation studies found the high cut-off less specific than first reported, so the PAS is best used to decide who needs imaging rather than as a diagnosis on its own.
Worked example
A 9-year-old has right lower quadrant tenderness (2), loss of appetite (1), vomiting (1), pain that moved from the umbilicus (1) and a white count of 13 × 10⁹/L (1), with no fever, no hop tenderness and neutrophils 7.0: PAS = 2 + 1 + 1 + 1 + 1 = 6 / 10 — equivocal (4–6); observe or image.
Sources: Samuel M. Pediatric appendicitis score. J Pediatr Surg 2002
Frequently asked questions
What Pediatric Appendicitis Score is high?
7 or more is high risk and usually needs a surgical review; 4–6 is equivocal (ultrasound or observation) and 3 or less makes appendicitis unlikely.
How is PAS different from the Alvarado score?
Both use similar items, but the PAS replaces rebound tenderness with pain on coughing, percussion or hopping (gentler in children) and was built specifically for children.
What is the hop test?
The child is asked to hop on the right leg; pain in the right lower abdomen when hopping, coughing or with gentle percussion counts as 2 points.
Can a low score rule out appendicitis?
It makes it unlikely but not impossible. Return or seek care if pain worsens, fever develops or the child will not walk normally.
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Clinical decision tool for education and for use by trained clinicians alongside clinical judgement — not a diagnosis and not a substitute for medical assessment. Scores validated in specific populations may not apply to every patient.