• General Paediatrics
• Outcomes research
• Respiratory

Assessing acutely unwell children with wheezing illness is a daily activity for an acute paediatrician. It is one of the most common presentations in unscheduled care.1 Judgements are made clinically on the severity of acute dyspnoea and treatment commenced. The response to treatment and the need to escalate the treatment or the decision to discharge or admit to hospital will depend on those clinical judgements. Research evidences for the efficacy and effectiveness of treatments are also based on clinical outcomes. These need to be considered sufficiently robust and valid to represent a primary outcome of sufficient quality to demonstrate differences in treatment. In acutely wheezy children, there have been many attempts to validate clinical scores for use both clinically and for research purposes. Indeed there are over 35 severity scores for use in assessing acutely dyspnoeic wheezy children.2

Are these measurements and scores sufficiently accurate for use clinically and for use in research? There are three key features to consider: validity, reliability and utility. Each one of these qualities is composed of a number of features. ‘Validity’ comprises face validity, content validity, construct validity and criterion-concurrent validity. ‘Reliability’ is composed of measurement error, interobserver reliability, intraobserver reliability, internal consistency and responsiveness. Utility is made up of suitability, age span covered, ease of scoring, skills required to complete the score, the ‘floor to ceiling effect’ and interpretability.2 It is clear that none of the scores used in this field have had full detailed development addressing all of these features.2

Thus, it is important to …