Summary of how the guidelines recommend spirometry could be used in the diagnosis and management of asthma in children
| Guideline [ref.] | Year of publication | Region | Recommendations for using spirometry | |
| To diagnose asthma (for children aged >5 years) | To monitor asthma | |||
| BTS/SIGN [11] | 2019 | UK | If probability of asthma is high, no testing may be required Spirometry is the recommended initial investigation If FEV1/FVC <LLN and BDR ≥12%, asthma is suspected If PEF monitoring over 2–4 weeks ≥20% variability, asthma is suspected | Spirometry or PEF monitoring at least annually Aim is to obtain a normal lung function expressed by FEV1 and/or PEF >80% predicted or best; anything less becomes significant |
| ERS task force for diagnosis of asthma [12] | 2021 | EU | Spirometry is the recommended initial investigation If FEV1/FVC or FEV1 <LLN or <80% predicted, BDR should be done; if BDR ≥12% and/or ≥200 mL, asthma is confirmed If spirometry normal, FENO should be done; if FENO is raised, PEF variability should be done; if PEF variability ≥12%, asthma is confirmed | Not applicable |
| ERS task force for monitoring asthma [13] | 2015 | EU | Not applicable | Spirometry with BDR at least annually or more frequently in children with reduced lung function and poor asthma control No recommendations for value interpretation PEF not recommended |
| GINA [1] | 2019, updated in 2022 | Global | Spirometry is the recommended initial investigation If abnormal, i.e. FEV1/FVC <LLN, and if FEV1 changes by >12% after 1) BDR or 2) trial of asthma preventer, or if 3) PEF variability >13%, then variable expiratory airflow (asthma) is confirmed | FEV1 recorded at the beginning of treatment, after 3–6 months of controller medication and then “periodically” Repeated spirometry every 1–2 years Advice to plot FEV1 and FEV1/FVC to assess trends |
| ICON paediatric asthma [9] | 2012 | Global | Lung function tests are supportive of diagnosis Spirometry with BDR is preferred to PEF measurements The following features would be suggestive of asthma: FEV1 <80% predicted with positive BDR expressed by FEV1 ≥12%, ≥200 mL or ≥10% predicted | Spirometry and PEF measurements (recommended for severe patients or with little perception of severity) No mention of how often these should be done |
| NAEPP [8] | 2007, updated in 2020 | US | Spirometry is recommended as the initial investigation Asthma diagnosis requires FEV1 and FEV1/FVC <80% predicted, also with positive BDR | Spirometry every 1–6 months PEF monitoring can also be included for patients with moderate or severe persistent asthma |
| NICE [10] | 2017, updated in 2021 | UK | Spirometry is recommended as the initial investigation When FEV1/FVC <70% predicted or <LLN, BDR should be done; a positive BDR confirms an asthma diagnosis If spirometry is normal, FENO should be done; if FENO raised and PEF variability >20%, asthma is confirmed | Either spirometry or PEF at each annual medical review No indications for value interpretation |
BTS/SIGN: British Thoracic Society/Scottish Intercollegiate Guidelines Network; ERS: European Respiratory Society; GINA: Global Initiative for Asthma; ICON: International consensus on; NAEPP: National Asthma Education and Prevention Program; NICE: National Institute for Health and Care Excellence; EU: European Union; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; LLN: lower limit of normal; BDR: bronchodilator response; PEF: peak expiratory flow; FENO: exhaled nitric oxide fraction.