FEV1/FVC Ratio

AKA: Modified Tiffeneau-Pinelli Index.
Context:
- output: Normal values are approximately 75%, indicating good lung function.
- It can (typically) be a Diagnostic Measure for Obstructive/Restrictive Lung Disease.
- It can (typically) quantify the proportion of vital capacity exhaled in the first second of forced expiration.
- …
Example(s):
- One that is calculated online (e.g. based on patient's age, sex, height, and ethnicity).
- An FEV1/FVC Ratio of 0.70 which can indicate lower than normal lung function, warranting further examination.
- An FEV1/FVC ratio of 0.80 can indicate healthy lung function.
- …
Counter-Example(s):
- FEV1/VC Index.
See: Spirometry, Forced Vital Capacity (FVC), Obstructive Lung Disease, Restrictive Lung Disease, Vital Capacity.

References

(Wikipedia, 2023) ⇒ https://en.wikipedia.org/wiki/FEV1/FVC_ratio Retrieved:2023-10-17.
- The FEV1/FVC ratio, also called modified Tiffeneau-Pinelli index, is a calculated ratio used in the diagnosis of obstructive and restrictive lung disease. It represents the proportion of a person's vital capacity that they are able to expire in the first second of forced expiration (FEV1) to the full, forced vital capacity (FVC). FEV1/FVC ratio first proposed by E.A. Haensler in 1950. The FEV1/FVC index should not be confused with the FEV1/VC index (Tiffeneau-Pinelli index) as they are differnet, although both are intended for diagnosing airway obstruction. Current recommendations for diagnosing pulmonary function recommend using the modified Tiffeneau-Pinelli index (also known as the Haensler index). This index is recommended to be represented as a decimal fraction with two digits after the decimal point (for example, 0.70). Normal values are approximately 75%. Predicted normal values can be calculated online and depend on age, sex, height, and ethnicity as well as the research study that they are based upon. A derived value of FEV1% is FEV1% predicted, which is defined as FEV1% of the patient divided by the average FEV1% in the population for any person of similar age, sex, and body composition.