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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 3 month - 6 years olds with acute stridor, barking cough, hoarseness, and respiratory distress - sometimes with URI symptoms.
    • Westley and other scoring systems attempted to differentiate infectious vs ipasmodic croup, and focus on the Infectious.
      • Many experts believe infectious and spasmodic are on the same disease spectrum.
    • Has been used (with moderate reliability) to assess for post-extubation upper airway obstruction.
    • Derived to measure transient clinical states between patients, and within the same patient over time. (Westley 1978)
    • Original study measured the clinical response of nebulized racemic epinephrine vs saline. It didn’t aim to create a prognostic scoring system.
      • Score is most applicable for research - other guidelines (e.g., from the Alberta Medical Association) are more relevant in the clinical setting.
    • 1 of 3 croup scoring systems to be externally validated.
    • “Mild,” “Moderate” and “Severe” classifications and treatments were developed years later.

    Designed to measure severity for research settings, but often applied to prognosticate. May be useful in determining treatment efficacy and patient disposition.

    About the Creator
    Dr. Terry Klassen
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      • Definitions of croup severity are neither widely accepted nor rigorously derived.
      • Oral, inhaled, or intramuscular corticosteroids are recommended for all patients with croup, even with barking cough alone.
        • Corticosteroids improve croup scores at 6 hours, reduce re-visits/re-admissions, and reduce ED/Hospital length of stay.
      • Consider the Alberta (Canada) Clinical Practice Guideline (see below) or institution-specific (e.g., Children’s Hospital Colorado) algorithms for more clinically relevant guidance of classification and treatment.


      Treatment algorithms differ among institutions; for the Alberta Group treatment algorithm.


      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 (Westley 1978) and follow-up validation studies (Super 1989) (Klassen 1999) 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 (i.e., spasmodic croup) through pre-enrollment standardized mist therapy for all patients.
        • Sample sizes were small, with 20 subjects in the original Westley, et. al. cohort, and 29 & 54 subjects in the 2 validation studies, respectively.
      • The range of values for each of the 5 items was arbitrary; based on the clinical consequences of the most critical form of each sign.
      • The primary outcome measure common to many studies is a reduction by 2 points, or return to a score of 0-1.
      • Studies using the modified Westley score (Super 1989) had great inter-rater reliability (weighted kappa of 0.75).
      • Inter-rater reliability analysis in demonstrated a weighted kappa of 0.95 ± 0.02 amongst research assistants and primary investigators. (Klassen 1999).
      • Improvement in score after treatment correlates with patient disposition -- and with “Global Assessment of Change” as rated by parents, ED docs, and research assistants. (Klassen 1999)


      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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