The EPICure study: Comparison of pediatric spirometry in community and laboratory settings

RATIONALE: Accuracy of spirometry testing is a prerequisite for its use as an objective outcome measure in large epidemiological studies. We compared spirometry measurements obtained by trained pediatricians in a variety of school settings with those obtained in the laboratory by respiratory physiologists. METHODS: Following a 3-day training course, three pediatricians carried out spirometry in children born extremely preterm (EP) and age matched controls in schools across the UK and Ireland (The EPICure study). A subgroup had repeated measurements in the laboratory. Spirometric flows and volumes were expressed as Z-scores. Bland-Altman analysis was used to calculate within-subject differences. RESULTS: Fifty children (40% boys), 37 (74%) of whom were born EP, with a mean age 10.8 years had paired spirometry results (average interval between tests: 20.3 weeks). There was no statistically significant difference between any of the outcome variables: mean (95% CI of difference) in Z-scores [school-laboratory]) being 0.0 (-0.1; 0.1) for FEV(1), 0.1 (-0.1; 0.3) for FVC, -0.1 (-0.3; 0.1) for FEF(25-75), and 0.0 (-0.3; 0.1) for FEV(1)/FVC. Within individuals, the 95% limits of agreement for repeated measures were within +/- 1 Z-score for FEV(1) and FVC, and within +/- 1.5 Z-score for FEF(25-75) and FEV(1)/FVC. CONCLUSION: With appropriate training, quality control, and support, pediatric spirometry can reliably be performed outside the lung function laboratory.