Oscillometry for the diagnosis of asthma in children: a systematic review

Clinical Snapshot

Key Findings

• P Value: Not reported in abstract

• Effect Size: Optimized BDR threshold: 17.0% decrease in R5 achieved 71.6% sensitivity and specificity

• Primary Outcome: Diagnostic accuracy of oscillometry using ERS thresholds showed zero sensitivity with high specificity (>85%)

• Nnt Or Sensitivity: Current ERS thresholds: 0% sensitivity, >85% specificity; Optimized thresholds: 68.6-73.6% sensitivity and specificity

• Confidence Interval: 95% CI 69.7-73.7% for optimized BDR threshold

Clinical Application

Oscillometry is feasible from 2 years of age, potentially offering advantages over spirometry in young children who cannot perform adequate spirometry Relevant to Australian paediatric respiratory practice; may inform future RACGP and specialist respiratory guidelines for childhood asthma diagnosis, particularly given PBS coverage considerations for asthma medications Children and young people from 2 years of age under investigation for asthma in primary and secondary care settings

Abstract

BACKGROUND: Diagnosing asthma in children and young people (CYP) remains challenging. Oscillometry is a promising tool and is feasible from 2 years of age. European Respiratory Society (ERS) technical standards and bronchodilator response (BDR) oscillometry thresholds have been published, but diagnostic accuracy is not established. METHODS: We systematically reviewed studies comparing oscillometry and spirometry in CYP under investigation for asthma. Reference standards were positive BDR or positive methacholine challenge test (MCT). Primary aims were to investigate the sensitivity and specificity of current ERS oscillometry thresholds (>40% decrease in resistance at 5 Hz (R 5), >50% increase in reactance at 5 Hz (X 5) or >80% decrease in the area under the reactance curve); secondary aims were to identify oscillometry threshold values optimising both sensitivity and specificity. RESULTS: 11 studies were included; six (n=992 CYP) utilised BDR and five (n=531 CYP) MCT as reference standard. Meta-analysis was not possible due to heterogeneity of results reported. In two studies using current ERS BDR thresholds, zero sensitivity and high specificity (>85%) were observed. In weighted regression analyses of BDR studies, a 17.0% decrease in resistance at 5-6 Hz had sensitivity and specificity of 71.6% (95% CI 69.7-73.7%); a 20.2% increase in X 5 had sensitivity and specificity of 68.6% (95% CI 66.6-70.8%). Similarly, 27.7% increase in R 5 had sensitivity and specificity of 73.6% (95% CI 71.9-75.3%) for MCT. CONCLUSION: Currently recommended ERS thresholds for oscillometry BDR have low sensitivity. Proposed thresholds for defining positive BDR and MCT by oscillometry require prospective validation and adoption of standards for measuring and reporting oscillometry parameters in future diagnostic comparative studies.

References

1. 1.Seneviratne, S. Y., Law-Gleen, S., Broomfield, J., Divall, P., Devani, P., Ducharme, F. M., & Gaillard, E. A. (2026). Oscillometry for the diagnosis of asthma in children: a systematic review. European Respiratory Review, 35(160). https://doi.org/10.1183/16000617.0293-2025