Sources of variation in forced expiratory volume in one second and forced vital capacity

Sources of variation in forced expiratory volume in one second and forced vital capacity.

Published prediction equations for lung function differ considerably, but the components of population variation responsible for the differences are unknown. Data were analysed for 6,323 never-smoking adults who did not report wheeze or asthma, from 42 centres participating in the European Community Respiratory Health Survey. Means and components of variance were estimated for males and females...

Obstructive ventilatory defect with normal forced expiratory volume in one second/vital capacity ratio.

Use of forced vital capacity and forced expiratory volume in 1 second quality criteria for determining a valid test

The 2005 American Thoracic Society (ATS)/European Respiratory Society (ERS) spirometry guidelines define valid tests as having three acceptable blows and a repeatable forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). The aim of this study was to determine how reviewer and computer-determined ATS/ERS quality could affect population reference values for FVC and FEV1. Spirome...

Effort and the forced expiratory volume in one second (FEV).

1. The relationship between volumes expired and the maximum intrathoracic pressures developed within the first second of expiration was examined in a group of healthy subjects and patients with airways obstruction who exhaled with varying degrees of effort. 2. The body plethysmographic method was used to ensure that expirations started from total lung capacity. 3. Three different types of volum...

Should forced expiratory volume in six seconds replace forced vital capacity to detect airway obstruction?

It has been suggested that forced expiratory volume in six seconds (FEV(6)) should be substituted for forced vital capacity (FVC) to measure fractions of timed expired volume for airflow obstruction detection. The present authors hypothesised that this recommendation might be questionable because flow after 6 s of forced expiration from more diseased lung units with the longest time constants w...