Spirometry Quality Grading
This grading is not available for tests made prior to May 18 2026 and when patients are using outdated versions of the app. These tests will instead only have a Good/Poor rating.
Spirometry results are assigned a quality grade (A–F) based on repeatability and adherence to technical standards. These criteria were developed and are endorsed by the American Thoracic Society (ATS) and the European Respiratory Society (ERS), ensuring they are scientifically validated and widely recognized.
Careportal displays a combined grade based on both FEV1 and FVC measurements. If the measurements receive different grades (e.g., FEV1 is graded A and FVC is graded B), the lower grade (B) is shown. This provides a conservative overall quality assessment of the spirometry session.
- Grade A: At least 3 acceptable maneuvers with repeatability within 0.150 L (for ages >6 years) or 0.100 L (for ages ≤6 years).
- Grade B: At least 2 acceptable maneuvers with repeatability within 0.150 L (for ages >6 years) or 0.100 L (for ages ≤6 years).
- Grade C: At least 2 acceptable maneuvers with repeatability within 0.200 L (for ages >6 years) or 0.150 L (for ages ≤6 years).
- Grade D: At least 2 acceptable maneuvers with repeatability within 0.250 L (for ages >6 years) or 0.200 L (for ages ≤6 years).
- Grade E: At least 2 acceptable maneuvers with repeatability exceeding 0.250 L (for ages >6 years) or 0.200 L (for ages ≤6 years). Alternatively, at least 1 acceptable maneuver.
- Grade F: No acceptable or usable maneuvers.
- Grade U (Unusable): No acceptable maneuvers, but at least 1 usable maneuver.
- Grades A, B, and C: Generally considered reliable for clinical interpretation.
- Grades D and E: Lower reliability; results should be used with caution and ideally repeated.
- Grade U: Results are not interpretable and should not be used for clinical decisions.
- Grade F: No usable data; the test must be repeated.
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