A clinical estimate of asthma severity using a clinical score and oxygen saturation measurements by pulse oximetry was carried out on a group of 41 children aged 3 years or older. The measurements were performed at the time of each child's admission to hospital with an acute asthma attack. The correlation coefficient (r) between the asthma score and the oxygen saturation was -0.76. For children older than 3 years, clinical scoring methods may have a place in the assessment of those with acute asthma, especially when they are receiving high flow oxygen treatment.