Centor Score Calculator
Calculate the Centor Score to assess the probability of streptococcal pharyngitis (strep throat) in patients with sore throat symptoms.
How to Use This Calculator
- Enter the patient's age in years
- Select whether the patient has a history of fever
- Indicate if cough is absent from the patient's symptoms
- Select whether tonsillar exudates are present
- Indicate if tender anterior cervical lymph nodes are present
- Click Calculate to see the Centor Score and strep throat probability
Formula Used
Centor Score = Age Score + History of Fever + Absence of Cough + Tonsillar Exudates + Tender Anterior Cervical Lymph Nodes
Where:
- Age Score = 1 point for ages 3-14, 0 points for ages 15-44, -1 point for ages 45+
- History of Fever = 1 point if present, 0 points if absent
- Absence of Cough = 1 point if cough is absent, 0 points if present
- Tonsillar Exudates = 1 point if present, 0 points if absent
- Tender Anterior Cervical Lymph Nodes = 1 point if present, 0 points if absent
Example Calculation
Real-World Scenario:
A 12-year-old patient presents with a sore throat, fever, and swollen lymph nodes. On examination, the physician notes tonsillar exudates but no cough.
Given:
- Patient Age = 12 years
- History of Fever = Yes (1 point)
- Absence of Cough = Yes (1 point)
- Tonsillar Exudates = Yes (1 point)
- Tender Anterior Cervical Lymph Nodes = Yes (1 point)
Calculation:
Centor Score = Age Score (1) + History of Fever (1) + Absence of Cough (1) + Tonsillar Exudates (1) + Tender Anterior Cervical Lymph Nodes (1)
Centor Score = 1 + 1 + 1 + 1 + 1 = 5
Result: A Centor Score of 5 indicates a 51-53% probability of streptococcal pharyngitis, with a recommendation to consider empiric antibiotic treatment.
Why This Calculation Matters
Practical Applications
- Helps clinicians determine the likelihood of strep throat infection
- Guides decisions about antibiotic prescriptions
- Reduces unnecessary antibiotic use and antibiotic resistance
- Identifies patients who need further testing (culture or rapid antigen test)
Key Benefits
- Provides evidence-based guidance for clinical decision-making
- Helps balance diagnostic accuracy with cost-effectiveness
- Reduces unnecessary testing and treatment
- Improves patient outcomes by targeting appropriate therapy
Common Mistakes & Tips
Frequently Asked Questions
References & Disclaimer
Medical Disclaimer
This calculator is for educational and informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. The Centor Score is a clinical decision aid and not a definitive diagnostic tool. Always seek the advice of a qualified healthcare provider with any questions you may have regarding a medical condition.
References
- Centor RM, et al. "Streptococcal pharyngitis in adults: Reliability of clinical diagnosis and the effect of treatment on the course of the illness." Ann Intern Med. 1981. - Original Centor Score publication
- Wigton RS, et al. "Use of clinical findings in the diagnosis of streptococcal pharyngitis." JAMA. 1986. - Validation of the Centor criteria
- Centers for Disease Control and Prevention (CDC) - Guidelines for streptococcal pharyngitis testing and treatment
Accuracy Notice
The Centor Score provides estimates of the probability of streptococcal pharyngitis based on clinical criteria. The actual probability may vary based on local prevalence, seasonality, and individual patient factors. This calculator should be used as a supplement to, not a replacement for, clinical judgment and appropriate diagnostic testing when indicated.
About the Author
Kumaravel Madhavan
Web developer and data researcher creating accurate, easy-to-use calculators across health, finance, education, and construction and more. Works with subject-matter experts to ensure formulas meet trusted standards like WHO, NIH, and ISO.