Calculate FEV1 % predicted using NHANES III reference equations for adults. Predicted FEV1 varies by age, height, sex, and race. FEV1 % predicted < 80% indicates below-normal expiratory flow and is used for GOLD COPD staging.
Predicted FEV₁: 3.55 L | GOLD stage: GOLD 1 (Mild) | SABA PRN; consider LAMA
FEV₁ ≥ 80% predicted is within the normal range; 70–79% is borderline; < 70% indicates mild to severe obstruction when combined with a reduced FEV₁/FVC ratio. GOLD staging requires a post-bronchodilator FEV₁/FVC < 0.70 (obstructive defect confirmed).
Reference: Hankinson JL, et al. Am J Respir Crit Care Med 1999;159:179–187 (NHANES III). GOLD 2024 Report.
Calculate FEV1 % predicted using NHANES III reference equations for adults. Predicted FEV1 varies by age, height, sex, and race. FEV1 % predicted < 80% indicates below-normal expiratory flow and is used for GOLD COPD staging
Each component has a specific meaning:
Note: Interpret the fev1 % predicted result against the thresholds and context described above.
Enter the NHANES III reference equations for the scenario you are assessing. Calculate FEV1 % predicted using NHANES III reference equations for adults. Predicted FEV1 varies by age, height, sex, and race. FEV1 % predicted < 80% indicates below-normal expiratory flow and is used for GOLD COPD staging. Use the fev1 % predicted result to inform your calculation.