Emergency and critical care
Alvarado score
The Alvarado score combines symptoms, signs and two laboratory findings into a likelihood of acute appendicitis. It is best used to identify the patient who does not need imaging and the one who probably does.
Enter the values
Result
0/ 10
Appendicitis unlikely
Appendicitis is unlikely. Consider discharge with clear safety-netting, or another diagnosis.
This calculator is provided for reference and education. It does not replace clinical assessment, examination, current guidelines, local protocol, or professional judgment. Verify every result before acting on it. Nirogix accepts no liability for clinical decisions made using this tool.
The formula
- Migration 1 · Anorexia 1 · Nausea or vomiting 1 · RIF tenderness 2 · Rebound 1 · Fever 1 · Leukocytosis 2 · Left shift 1
- Total range 0 to 10. The mnemonic is MANTRELS.
When to use it
- Right iliac fossa pain where the diagnosis is uncertain
And when not to
- It performs less well in women of childbearing age, in children, and in the elderly.
- A low score does not exclude appendicitis in a patient who looks unwell.
References
- A practical score for the early diagnosis of acute appendicitis — Alvarado A, Annals of Emergency Medicine, 1986
Last reviewed 07/09/2026.
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These calculators are free and always will be. We also build Nirogix, a hospital management system for Indian clinics and hospitals. The same calculations are planned inside the consultation record, pre-filled from the chart.