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    Westley Croup Score

    Quantifies croup severity (although mainly used for research, not clinically).
    When to Use
    Why Use
    • Consider croup (laryngotracheobronchitis) in patients aged 6 months to 6 years with acute-onset syndrome of stridor, barking cough, hoarseness, and respiratory distress, sometimes concurrently with URI symptoms. 
    • Croup is a clinical diagnosis based on history and physical exam. Severity of croup can be quantified via the Westley Croup Score, though, clinically it is not used to guide therapy. Instead, it is used to measure a patient’s response to therapy.
    • Researchers have attempted to separate this entity from “spasmodic” (i.e., recurrent, short-lived) croup, which may be due to allergic reaction of viral antigens.
      • Presentation and pathology may be the same, which makes response to treatment difficult to determine.  As a result, many authorities consider these entities part of the same disease spectrum
    • This score is traditionally used for clinical research purposes in order to track patient response over time to treatment.
    • Has been used with moderate reliability to assess for post-extubation upper airway obstruction.
    • The original score (Westley 1978) was derived to objectively measure a clinical state in order to allow comparisons over time in response to treatment.
    • Developed to compare the response of nebulized racemic epinephrine versus saline, not to derive a prognostic scoring system.
    • The range of values for each of the five items was arbitrary and each was weighted based on the clinical implications of the most critical form of each sign.
    • Follow-up studies demonstrated construct validity (Klassen 1999), with multiple studies showing high inter-rater reliability (Klassen 1999, Super 1989).
    • Most commonly used scoring system for croup.
    • Designed to measure severity for research settings, but often applied to prognosticate. May be useful in determining treatment efficacy and patient disposition.
    • Has fair inter-rater reliability in clinical users (though better in research studies).
    • Change in score correlates well with patient disposition and global assessment as rated by both parents and ED physicians.
    • Continues to be used in studies for treatment of croup since its validity and reliability among users were demonstrated.
    With agitation
    At rest
    With agitation
    At rest
    Markedly decreased


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    • Treatment algorithms differ among institutions.
    • A 2012 Cochrane review showed that glucocorticoids improved the Westley Croup Score at 6 and 12 hours, prevented repeat visits, and decreased length of stay (Russell 2011).
    • The optimal dose of glucocorticoid has not yet been determined, though conventionally, the dose used is 0.6mg/kg of dexamethasone, administered IV or orally (Russell 2011).
    • A small study in Thailand compared 0.15mg/kg to 0.6mg/kg and found no difference in Westley Croup Score, though this was a small study (n = 41) and patients also received racemic epinephrine nebulization prior to steroid administration (Chubb-Uppakarn 2007).

    Critical Actions

    The Westley Croup Score was designed to track changes in the presentation of croup over time, and is primarily used in research studies.  Croup remains a clinical diagnosis, with the hallmark symptoms of barky cough, hoarse voice, with or without stridor.


    5 items using a Likert-type scale with zero representing the normal state. Points assigned as above.

    Facts & Figures

    Score interpretation*:

    Level of Severity Characteristics Corresponding Westley
    Croup Score
    Mild Occasional barking cough 0-2
    None - limited stridor at rest
    None to mild suprasternal and/or intercostal indrawing
    (retractions of the skin of the chest wall)
    Moderate Frequent barking cough 3-5
    Easily audible stridor at rest
    Suprasternal and sternal wall retraction at rest
    Little to no distress or agitation
    Severe Frequent barking cough 6-11
    Prominent inspiratory and occasionally expiratory stridor
    Marked sternal wall retractions
    Significant distress and agitation
    Impending Respiratory
    Barking cough (often non prominent) 12-17
    Audible stridor at rest (occasionally hard to hear)
    Sternal wall retractions (may not be marked)
    Lethargy or decreased level of consciousness
    Often dusky complexion without supplemental oxygen

    *Adapted from Bjornson 2005.


    • The “Stridor” and “Retractions” items were modified in the 2 validation studies with the intention of increasing inter-rater reliability.
      • Modified “Stridor” item used in 2 validation studies.
    Validated “Stridor” Item**
    None 0
    At rest, with stethoscope +1
    At rest, without stethoscope +2

    **Adapted from Super 1989.

    • Differing definitions of “Retractions” used in original Westley score vs 2 validation studies.
    Definition of 'Retractions' item
    Westley 1978 4-point scale (as above) otherwise unspecified
    Super 1989 Take highest of each independently scored site (i.e., alar, intercostal,
    supraclavicular, & subcostal) on the 4-point scale
    Klassen 1999 Severity at the intercostal & subcostal regions on 4-point scale

    Evidence Appraisal

    • Methodology for original and follow-up validation studies (Klassen 1999, Super 1989) was rigorous: prospective double-blind, randomized, placebo-controlled trials with a stringent definition of croup, and exclusion of the most mild or short-lived cases through pre-enrollment standardized mist therapy for all patients.
    • The primary outcome common to many treatment trials that used the Westley Croup Score is a positive clinical response defined as a reduction in the score by 2 points, or return to a score of 0-1.
    • Mild, moderate, and severe classifications and standardized treatments were studied and developed years later.
    • In the inter-rater reliability analysis performed by Super et al (1989), investigators had identical scores in 75% cases while the remaining scores different by only one unit, for a weighted kappa of 0.75.
    • Inter-rater reliability analysis in Klassen et al (1999) demonstrated a weighted kappa of 0.95 ± 0.02 amongst research assistants and primary investigators.
    • Since 1994, the score has been further validated and is the main scoring criteria used in evaluation of the patient’s response to treatment in clinical trials (Russell 2011).
    • In 2012, the Cochrane group updated the meta-analysis of glucocorticoids for croup. They identified 41 trials of glucocorticoids versus placebo or any other treatment modality. Their analysis showed an improved Westley Croup Score for patients at 6 and 12 hours that was significant. The Westley Croup Score was considered a primary outcome. Secondary outcomes included length of stay and use of another treatment modality (Russell 2011).


    Dr. Terry Klassen

    About the Creator

    Terry Klassen, MD, is the CEO and Scientific Director for the Children’s Hospital Research Institute of Manitoba. He is also head of the Department of Pediatrics and Child Health and scientific director of the George and Fay Yee Centre for Healthcare Innovation at the University of Manitoba. Dr. Klassen co-founded StaR Child Health to improve child-focused randomized control trial design, implementation and publication.

    To view Dr. Terry Klassen's publications, visit PubMed

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