Moore Vicky C, Parsons Nick R, Jaakkola Maritta S, Burge Cedd B S G, Pantin Charles F, Robertson Alastair S, Burge P Sherwood
Occupational Lung Disease Unit, Department of Respiratory Medicine, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK.
J Asthma. 2009 Nov;46(9):961-6. doi: 10.3109/02770900903229677.
Portable lung function logging meters that allow measurement of peak expiratory flow (PEF) and forced expiratory volume in 1 second (FEV(1)) are useful for the diagnosis and exclusion of asthma. The aim of this study was to investigate the within and between-session variability of PEF and FEV(1) for four logging meters and to determine the sensitivity of meters to detect FEV(1) and PEF diurnal changes.
Thirteen assessors (all hospital staff members) were asked to record 1 week of 2-hour PEF and FEV(1) measurements using four portable lung function meters. Within-session variability of PEF and FEV(1) were compared for each meter using a coefficient of variation (COV). Between-session variability was quantified using parameter estimates from a cosinor analysis which modeled diurnal change for both lung function measures and also allowed for variation between days for individual sessions.
The mean within-session COV for FEV(1) was consistently lower than that for PEF (p < 0.001). PEF showed a higher but not significantly different (p = 0.068) sensitivity for detecting diurnal variation than FEV(1). PEF was also slightly more variable between days, but not significantly different than FEV(1) (p = 0.409). PEF and FEV(1) diurnal variability did not differ between the 4 meters (p = 0.154 and 0.882 respectively), but within-session FEV(1) COV differed between meters (p = 0.009).
PEF was marginally more sensitive to within-day variability than FEV(1) but was less repeatable. Overall, differences between the 4 meters were small, suggesting that all meters are clinically useful.
可测量呼气峰值流速（PEF）和一秒用力呼气容积（FEV₁）的便携式肺功能记录仪对哮喘的诊断和排除很有用。本研究的目的是调查四种记录仪的PEF和FEV₁在不同时间段内及不同测量之间的变异性，并确定这些仪器检测FEV₁和PEF昼夜变化的敏感性。
邀请13名评估人员（均为医院工作人员）使用四种便携式肺功能仪记录1周内每天2小时的PEF和FEV₁测量值。使用变异系数（COV）比较每种仪器的PEF和FEV₁在测量过程中的变异性。通过余弦分析的参数估计来量化不同测量之间的变异性，该分析对两种肺功能指标的昼夜变化进行建模，同时也考虑了各个测量时间段之间的差异。
FEV₁在测量过程中的平均COV始终低于PEF（p < 0.001）。PEF在检测昼夜变化方面表现出更高但无显著差异（p = 0.068）的敏感性。PEF在不同日期之间的变异性也略高，但与FEV₁无显著差异（p = 0.409）。4种仪器的PEF和FEV₁昼夜变异性无差异（分别为p = 0.154和0.882），但不同仪器的测量过程中FEV₁的COV存在差异（p = 0.009）。
PEF对日内变异性的敏感性略高于FEV₁，但重复性较差。总体而言，4种仪器之间的差异较小，表明所有仪器在临床上都有用。
