Asthma is the most common non-communicable disease in children, but there is no single test available to confirm the diagnosis. In most cases, the diagnosis in children is made in non-specialist settings on the basis of clinical history and physical examination alone. 1 Danvers L Lo DKH Gaillard EA The role of objective tests to support a diagnosis of asthma in children.

Paediatr Respir Rev. 2020; 33: 52-57

Lingering respiratory symptoms, such as prolonged cough, resulting from viral respiratory tract infections, are common in children 2 Chang AB Oppenheimer JJ Weinberger M et al. Etiologies of chronic cough in pediatric cohorts: CHEST guideline and expert panel report.

Chest. 2017; 152: 607-617

and often wrongly attributed to asthma. 3 Jurca M Goutaki M Latzin P Gaillard EA Spycher BD Kuehni CE Isolated night cough in children: how does it differ from wheeze?.

ERJ Open Res. 2020; 6: 00217-02020

However, non-specialists frequently refrain from diagnosing asthma in children to avoid giving them a potentially life-long diagnostic label that could affect future job choices. 4 Lo D Beardsmore C Roland D et al. Spirometry and FeNO testing for asthma in children in UK primary care: a prospective observational cohort study of feasibility and acceptability.

Br J Gen Pract. 2020; 70: e809-e816

As a result, substantial over-diagnosis and under-diagnosis of asthma has been confirmed by several international studies. 5 Yang CL Simons E Foty RG Subbarao P To T Dell SD Misdiagnosis of asthma in schoolchildren.

Pediatr Pulmonol. 2017; 52: 293-302

, 6 Looijmans-van den Akker I van Luijn K Verheij T Overdiagnosis of asthma in children in primary care: a retrospective analysis.

Br J Gen Pract. 2016; 66: e152-e157

Both are problematic. Over-diagnosis results in the inappropriate prescription of asthma medications associated with potential side-effects and increased health-care costs. Conversely, under-diagnosis often results in poor quality of life.