Summary of Recommendations

Document Overview

Design and created by Guideline Central in participation with the Infectious Diseases Society of America.

Group A Streptococcal (GAS) Pharyngitis: Risk Assessment Using Clinical Scoring Systems in Children and Adults

Infectious Diseases Society of America

Publication Date: Oct 14, 2025

Page Last Updated: May 6, 2026

Table 2. Clinical Scoring for Predicting Group A Streptococcal Pharyngitis

Feature	Centor	Score	McIsaac	Score	FeverPAIN*	Score
Viral Symptoms	Absence of Cough	1	Absence of Cough	1	Absence of Cough or Coyrza	1
Cervical Adenopathy	Swollen tender anterior cervical nodes	1	Swollen tender anterior cervical nodes	1	N/A	0
Fever	>100.4oF (38oC)	1	>100.4oF (38oC)	1	Febrile in past 24 h	1
Tonsillar Appearance	Tonsillar Exudate or swelling	1	Tonsillar Exudate or swelling	1	Inflamed Tonsils	1
Tonsillar Appearance	Tonsillar Exudate or swelling	1	Tonsillar Exudate or swelling	1	Purulent Tonsils	1
Duration	N/A		N/A		<3 days since symptom onset	1
Age	N/A	0	3 y – 14 y	1	N/A	0
			15 y – 44 y	0
			>45 y	-1
Risk Stratification	Points	% Strep	Points	% Strep	Points	% Strep
Low Risk	0-1	7-12%	0-1	7.6-13.1%	0-1	1-10%
Intermediate Risk	2-3	21-38%	2-3	20.8-33.6%	2-3	11-35%
High Risk	4	57%	4-5	50.7-69.3%	4-5	51%-53%

* We did not find evidence that FeverPAIN has been compared to clinician judgement alone and therefore we did not include this scoring system in our analysis.
Columns show three scoring systems and the clinical features included in calculating the risk of testing positive for detection of GAS for each accumulated score (% Strep).

Recommendation Grading

Document Overview

Document Title: Group A Streptococcal (GAS) Pharyngitis: Risk Assessment Using Clinical Scoring Systems in Children and Adults

Authoring Society: Infectious Diseases Society of America

Endorsing Societies

American Society for Microbiology

Society of Infectious Diseases Pharmacists

Document Publication Date: Oct 14, 2025

Page Last Reviewed/Updated: May 6, 2026

Document Type: Guideline

Country of Publication: United States

Full Text Freely Available: Yes

Full Text Guideline: www.idsociety.org/practice-guideline/streptococcal-pharyngitis2/

Source Citation: Linder JA, Watson ME, Wessels MR, et al. Clinical Practice Guideline Update by the Infectious Diseases Society of America on Group A Streptococcal (GAS) Pharyngitis. Idsociety.org. Published 2025. https://www.idsociety.org/practice-guideline/streptococcalpharyngitis2/

Document Scope, Criteria, and Use Cases

Document Objectives: This publication represents the first part of an update to the clinical practice guideline on the diagnosis and management of group A streptococcal (Streptococcus pyogenes or GAS) pharyngitis, developed by the Infectious Diseases Society of America (IDSA). Diagnosis of GAS pharyngitis by clinician judgement alone is unreliable, and unselective testing incurs cost and inconvenience for individuals at low risk of having GAS infection. Clinical scoring systems have been used to quantify the probability of a positive GAS throat culture based on standardized criteria such as the presence of fever; tonsillar enlargement or exudate; tender and enlarged anterior cervical lymph nodes; and the absence of cough. The goal of this paper is to determine whether a scoring system should be used to decide which patients should have a diagnostic test performed by rapid antigen detection test (RADT), molecular methods, and/or throat culture. We performed a systematic review of randomized and non-randomized studies that compared the use of a clinical scoring system to clinician judgement alone in predicting the outcome of a throat culture. Evidence from studies in children and adults suggests the diagnostic accuracy of a clinical scoring system is comparable to or slightly higher than clinician judgement alone. However, the studies are limited due to small size, lack of uniformity in outcome measures, and incomplete data. The consensus of the panel is that the balance of benefits and harms favors use of a clinical scoring system as part of the evaluation of patients with sore throat. The principal utility of using a scoring system is to identify patients with low probability of GAS pharyngitis and to reduce unnecessary testing.

Scope: Assessment and Screening, Diagnosis, Management

Diseases/Conditions (MeSH)

D013290 - Streptococcal Infections

D025362 - Streptogramin Group A

D013297 - Streptococcus pyogenes

D013290 - Streptococcal Infections

D025362 - Streptogramin Group A

D013297 - Streptococcus pyogenes

Keywords: Group A streptococcal pharyngitis, Streptococcus pyogenes, strep pharyngitis

Target Patient Population: Children and adults with sore throat

Target Provider Population: Primary care providers and specialists caring for children and adults with sore throat

Inclusion Criteria: Male, Female, Adolescent, Adult, Child, Older Adult

Health Care Settings: Ambulatory

Intended Users: Nurse, Nurse Practitioner, Physician, Physician Assistant

Recommendation Development Processes & Methodology

Supplemental Methodology Resource: Data Supplement