Centor Strep Pharyngitis Criteria With McIsaac Modification

 

Input
 

Age		mo yr
Temperature		degC degF
Cough	Yes (0)
	No (1)
Tender Anterior Cervical Nodes	Yes (1)
	No (0)
Tonsillar Swelling or Exudate	Yes (1)
	No (0)

 

Result
 

Score		# index none number points score

 

Sore Throat Score

 

0 points:	2-3% chance of strep; no culture or antibiotics
1 point:	4-6% chance of strep; no culture or antibiotics
2 points:	10-12% chance of strep; culture and treat if positive
3 points:	27-28% chance of strep; culture and treat if positive
4 to 5 points:	38-63% chance of strep; culture and treat with antibiotic on clinical grounds

 

 

 

 
Equations used
 

Score = AgeFactor + TemperatureFactor + Cough + Tender Anterior Cervical Nodes + Tonsillar Swelling or Exudate

 

 

Calculation Details and Variables

• AgeFactor is assigned values by this ordered logic:
  • If Age ≥45 yr AgeFactor = -1
  • Else if Age ≥15 yr AgeFactor = 0
  • Else AgeFactor = 1.
• TemperatureFactor is assigned values by this ordered logic:
  • If Temperature >38 degC TemperatureFactor = 1
  • Else TemperatureFactor = 0.
• Equation parameters such as Cough, have two or more discrete values that may be used in the calculation. The numbers in the parentheses, e.g. (0), represent the values that will be used.

 

References

1. McIsaac WJ, White D, Tannenbaum D, Low D. A clinical score to reduce unnecessary antibiotic use in patients with sore throat. Can Med Assoc J. 158(1), 75-83, 1998. PubMed ID: 9475915
2. McIsaac WJ, Goel V, To T, Low DE. The validity of a sore throat score in family practice. CMAJ. 2000; 163: 811-5. PubMed ID: 11033707
3. Fine AM, Nizet V, Mandl KD. Large-scale validation of the Centor and McIsaac scores to predict group A streptococcal pharyngitis. Arch Intern Med. 2012 Jun 11;172(11):847-52. PubMed ID: 22566485