mdcalc.com | Alvarado Score for Acute Appendicitis

Signs
Right Lower Quadrant Tenderness?	Yes +2
Rebound Tenderness?	Yes +1
Elevated Temperature (37.3 °C or 99.1 °F)?	Yes +1
Symptoms
Migration of Pain to the Right Lower Quadrant?	Yes +1
Anorexia?	Yes +1
Nausea or Vomiting?	Yes +1
Laboratory Values
Leukocytosis > 10,000?	Yes +2
Leukocyte Left Shift?	Yes +1
Score	points

As the Alvarado Score is numerical, it has been evaluated for ruling in and ruling out appendicitis. Studies ruling out appendicitis (using Alvarado < 3-4) have a sensitivity of 96%; studies ruling in appendicitis (using Alvarado > 6-7) have a sensitivity of 58-88%, depending on the study and score cutoffs used. The 2007 McKay study (see below) recommends CT scan for Alvarado 4-6, surgical consultation for Alvarado ≥ 7, and for Alvarado ≤ 3, no CT for diagnosing appendicitis, as appendicitis is unlikely.

Alvarado Score for Acute Appendicitis