Adult pharyngitis · Clinical score
The Centor score helps emergency physicians, PAs, NPs, and residents risk-stratify adult pharyngitis for Group A Streptococcus (GAS). Its four clinical findings turn a bedside assessment into a decision-support signal for when to test and when treatment may be considered; it does not diagnose strep throat on its own.
Rule anatomy
04
original criteria
one point each
How to read the score
Centor was developed for patients with acute pharyngitis and uses the history and examination to estimate the likelihood of GAS. The original score is four binary criteria, each worth +1: tonsillar exudates, tender anterior cervical lymphadenopathy, fever above 38°C, and absence of cough.
A score can focus the next step, but clinical context comes first. Clear viral symptoms generally do not need GAS testing; when viral symptoms are absent, a clinical examination alone cannot reliably distinguish viral from GAS pharyngitis. Follow current CDC guidance and your institutional pathway, and reserve antibiotics for confirmed GAS unless local guidance specifically supports another approach.
Original Centor criteria
These are the original adult criteria used by the linked in-app calculator. Each positive finding adds one point to a total from 0 to 4.
Visible tonsillar exudate or swelling contributes one point. Record the finding from the current oropharyngeal examination.
Tender anterior cervical lymphadenopathy contributes one point. This is distinct from nonspecific neck discomfort or posterior adenopathy.
A documented or reported temperature above 38°C (100.4°F) contributes one point. Use the clinical history and measurement available for the encounter.
No cough contributes one point. Cough, rhinorrhea, hoarseness, oral ulcers, or conjunctivitis should also raise the possibility of a viral syndrome.
Modified Centor · McIsaac
The Modified Centor score adds an age adjustment to the original four criteria. It is commonly described as the McIsaac modification and is shown here for reference.
The linked in-app calculator is intentionally adult-only: it documents and scores the original four-criterion adult tool, does not add this age adjustment, and is not validated in children. Do not use the in-app result as a pediatric score.
Clinical decision support
The traditional adult Centor action bands below describe the usual testing and treatment pathway. They are decision support, not automatic orders.
Lower score
In the Centor decision pathway, this is the low-risk band. Do not treat the score as a substitute for assessing viral features, alternative diagnoses, or a concerning examination.
Intermediate score
Obtain a rapid antigen detection test (RADT) and treat confirmed Group A Streptococcus according to local protocol. A negative result may require age- and guideline-specific follow-up.
Higher score
Use a rapid antigen detection test and consider empiric antibiotics only according to local protocol, patient factors, and the broader clinical picture.
Current CDC guidance emphasizes that patients with clear viral symptoms do not need GAS testing, that testing is needed when viral symptoms are absent because examination alone cannot distinguish causes, and that antibiotics are for confirmed GAS. Check the current local or organizational guideline before release or clinical use.
Open the calculator
Tick the four adult Centor criteria and watch the total and action band update live. The in-app calculator is account-gated and does not persist the score, so you can move quickly without creating a patient record.
Open the Centor calculator →Informational only. Not a substitute for clinical judgement. Not a patient record — Centor scores are not persisted; a refresh clears the result. Derived for adults with acute pharyngitis; not validated in children. Always pair with your institution’s pharyngitis pathway and clinical gestalt.