ROUNDS·
Surgery

Alvarado Score Calculator

Estimates the probability of acute appendicitis using symptoms, signs, and basic labs.

Migration of pain to right lower quadrant+1
Anorexia+1
Nausea or vomiting+1
Right lower quadrant tenderness+2
Rebound pain+1
Elevated temperature (>37.3°C)+1
Leukocytosis (>10,000/mm³)+2
Left shift / neutrophilia (>75%)+1

What is the Alvarado Score?

The Alvarado Score, developed by Alfredo Alvarado in 1986, combines symptoms, signs, and basic labs into a 10-point score estimating the probability of acute appendicitis.

Interpretation

ScoreProbability
≤4Unlikely
5–6Equivocal — possible appendicitis
7–10Probable — surgical consultation

Limitations

Performance varies by age and sex — it tends to be less reliable in women (due to gynecological mimics) and young children. It supports, but doesn't replace, clinical judgment and imaging where indicated.

References

Alvarado A. A practical score for the early diagnosis of acute appendicitis. Ann Emerg Med. 1986.

Frequently Asked Questions

Can Alvarado Score rule out appendicitis on its own?

No — a low score makes appendicitis less likely but doesn't fully exclude it. Clinical judgment and, often, imaging are still used alongside the score.

Is Alvarado Score equally accurate in everyone?

No — performance varies somewhat by age and sex, performing less well in women and young children, so use it as one input rather than a stand-alone diagnostic tool.

What replaced left shift if a differential isn't available?

Some modified versions of the score omit the left-shift criterion when a differential count isn't readily available, scoring out of a slightly adjusted maximum.