Centor Scrore Calculator

Centor Score Calculator – Assess the Risk of Strep Throat Quickly

The Centor Score Calculator is a clinical decision tool used to estimate the likelihood of Group A Streptococcal pharyngitis (strep throat) in patients presenting with sore throat symptoms. It helps healthcare professionals determine whether antibiotics or further testing are needed.


What Is the Centor Score?

The Centor Score assigns points based on specific symptoms and clinical findings to assess the probability of a bacterial (not viral) sore throat. It was developed to help reduce unnecessary antibiotic prescriptions by identifying patients who are more likely to benefit from treatment.


Criteria Used in the Calculator

The calculator evaluates four or five clinical factors, depending on whether you’re using the original or modified version:

Centor Criteria:

  1. Fever (Temperature >38°C / 100.4°F)
  2. Absence of Cough
  3. Tonsillar Exudates or Swelling
  4. Tender Anterior Cervical Lymph Nodes

Modified Centor (McIsaac) adds:

5. Patient’s Age

Age Range Points 3–14 years +1 15–44 years 0 45+ years –1 How the Centor Score Is Interpreted

Score Estimated Risk of Strep Clinical Action 0–1 <10% No testing or antibiotics 2 ~11–17% Consider rapid test or culture 3 ~28–35% Test and consider treatment 4+ ~51% or higher Consider empiric antibiotics or test The Centor Score is not a diagnostic tool, but a guideline to help decide whether to test further or treat empirically.


Why Use a Centor Score Calculator?

  • Quick decision support in outpatient and urgent care settings
  • Reduces unnecessary antibiotics, limiting resistance
  • Improves patient triage in busy clinical environments
  • Supports best practices in evidence-based medicine

This tool is widely used by general practitioners, pediatricians, and family doctors.


Who Should Use It?

  • Medical practitioners and clinicians
  • Urgent care and family medicine staff
  • Medical students and residents
  • Clinical educators and healthcare websites


Common Questions

Can I use the Centor Score for children?

Yes, the Modified Centor Score (McIsaac) adjusts for age, making it more suitable for children as young as 3 years old.

Does a high score mean I definitely have strep throat?

Not necessarily. It means your risk is higher and further testing or treatment is more likely to be needed.

Is a sore throat always caused by strep?

No. Most sore throats are viral. The Centor Score helps estimate the likelihood of a bacterial cause.

Disclaimer

This tool is for informational and educational purposes only and should not replace clinical judgment or a professional diagnosis. Always consult a healthcare provider for treatment decisions.


The Centor Score Calculator is a fast and reliable way to determine if a sore throat is likely bacterial and whether antibiotics or testing are appropriate. It supports better prescribing practices and helps ensure timely and appropriate patient care.

Add this calculator to your medical website or clinic toolset to improve diagnostic efficiency and support antimicrobial stewardship.