Forced Expiratory Volume in 1 Second to Slow Vital Capacity Ratio Measurement

**Semantic type:** Diagnostic Procedure

**Definition:** A relative measurement (ratio or percentage) of the forced expiratory volume during the first second of exhalation to the largest observed expired volume during a slow vital capacity maneuver.

**Synonyms:** - FEV1/SVC - FEV1/SVC - FEV1/SVC - FEV1SVC