Table 3. Correlation and agreement between measurement of PEF when standing and when sitting

	Women	Men	All
Pearson’s correlation coefficient	0.94	0.92	0.95
Bias between readings (slope, intercept)	1.00 (1.00, 5.68)	0.99 (1.04, −6.11)	1.00 (1.03, −4.12)
Agreement^a (95% CI)	0.94 (0.912 to 0.959)	0.92 (0.88 to 0.95)	0.95 (0.938 to 0.964)
Limits of agreement (95% CI)	5.81 (−53.60 to 65.22)	12.39 (−71.51 to 96.28)	8.72 (−62.66 to 80.10)

^aLin’s concordance coefficient (Pearson’s correlation coefficient x bias between readings). PEF = peak expiratory flow.