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Pneumology

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Pneumology calculator

Simplified Spirometry Interpretation

Teaching-style spirometry pattern interpretation.

Educational tool • no LLN / no z-score

Simplified Spirometry Interpretation

Enter only FEV1 % predicted, FVC % predicted, and the FEV1/FVC ratio to obtain a quick teaching-style conclusion: obstructive, restrictive, mixed, or normal pattern.

Student rule

1

FEV1/FVC < 70% → obstructive component.

2

FVC < 80% + normal ratio → probable restrictive pattern.

3

FEV1/FVC < 70% + FVC < 80% → possible mixed pattern.

1

Enter values

You can enter the ratio as a percentage, for example 65, or as a decimal, for example 0.65.

Teaching thresholds used

Default: FEV1/FVC <70% and FVC <80%. You can adjust the thresholds for teaching or exam practice.

The result will appear here

Enter the three values and press “Interpret”.

Severity by FEV1 % predicted

≥70%mild
50–69%moderate
35–49%severe
<35%very severe

Note: this version is intentionally simplified for students. True restriction is confirmed by low TLC, not by FVC alone.

Educational tool. It does not replace full ERS/ATS interpretation or clinical correlation.

Note: MedicalC is NOT medical software and does NOT issue diagnoses or treatment recommendations. The calculators are for educational and informational purposes, use published medical formulas, and are not a substitute for medical consultation. Results should be interpreted by professionals.Read the full disclaimer.