The Westley croup score is validated and commonly used in clinical practice (Table 1). Children with croup can be divided into four levels of severity [7,8]:
85% of children have mild croup. Around 5% of children with croups require admission to hospital and of these 1-3% require intubation. In a 10-year study of those intubated there was 0.5% mortality rate. Uncommon complications include pneumonia and bacterial tracheitis. [9]
| Score | Stridor | Retractions | Air Entry | SaO2 <92% | Level of consciousness |
| 0 | None | None | Normal | None | Normal |
| 1 | Upon agitation | Mild | Mild decrease | ||
| 2 | At rest | Moderate | Marked decrease | ||
| 3 | Severe | ||||
| 4 | Upon agitation | ||||
| 5 | At rest | Decreased |