Centor Score (modified by McIsaac)

The Centor score was developed to predict the probability of a positive culture for group A β-hemolytic streptococci in patients with pharyngitis. The modification by McIsaac et al. also takes the patient’s age into account. The score can only be applied to acute pharyngitis within the first three days and is only valid for patients ≥ 3 years.

Age

years

Temperature ≥ 38 °C

Yes No

Cough

Yes No

Swollen, tender anterior cervical nodes

Yes No

Tonsillar swelling or exudate

Yes No

(modified by McIsaac)

Interpretation

Score	Probability of group A β-hemolytic streptococci	Recommendation
≤ 0	1-2.5 %	No further diagnostics or antibiotic therapy recommended
1	5-10 %	No further diagnostics or antibiotic therapy recommended
2	11-17 %	Perform culture/rapid test, antibiotic therapy recommended if positive
3	28-35 %
≥ 4	51-53 %	Empirical antibiotic therapy recommended

References

Centor RM, Witherspoon JM, Dalton HP et al. The diagnosis of strep throat in adults in the emergency room. Med Decis Making 1981; 1: 239-246
McIsaac WJ, White D, Tannenbaum D et al. A clinical score to reduce unnecessary antibiotic use in patients with sore throat. CMAJ 1998; 158: 75-83
McIsaac WJ, Kellner JD, Aufricht P et al. Empirical validation of guidelines for the management of pharyngitis in children and adults. JAMA 2004; 291: 1587-1595