End
Modified Centor (McIsaac) Score
Estimates probability of Group A Strep (GAS) pharyngitis and suggests management course.
Patient Age
GAS is more common in children
Tonsillar Exudate / Swelling
Presence of white patches or swelling
Swollen/Tender Ant. Cervical Nodes
Lymphadenopathy in the neck
History of Fever / Temp >38°C
>100.4°F during the illness
Absence of Cough
Cough suggests viral etiology
0
Score
Calculating…
GAS Probability: -%
| Score | Risk | Recommendation |
|---|---|---|
| ≤ 1 | Low | No testing or antibiotics required. |
| 2 – 3 | Moderate | Rapid Strep Test (RADT) or Culture recommended. |
| ≥ 4 | High | Test and/or consider empiric antibiotics. |
1
Viral Signs: If rhinorrhea, conjunctivitis, or diarrhea are present, viral etiology is much more likely.
2
Age < 3: GAS is extremely rare in children under 3 years old; scoring is less reliable in this group.
3
Culture vs RADT: In children and adolescents, a negative RADT (Rapid Test) should be confirmed by throat culture.
4
Rheumatic Fever: The primary goal of treatment is to prevent Acute Rheumatic Fever (ARF), not necessarily to shorten symptom duration.
