TABLE 3

Estimated changes of forced expiratory volume in 1 s z-scores with birth cohort in the total population

	Males				Females
Birth cohort	n	Coefficient	95% CI	p-value	n	Coefficient	95% CI	p-value
1894–1904	469	-	-	-	640	-	-	-
1905–1914	517	−0.05	(−0.18–0.08)	0.440	720	0.19	(0.06–0.31)	<0.001
1915–1924	674	0.19	(0.07–0.31)	<0.001	790	0.31	(0.19–0.43)	<0.001
1925–1934	1552	0.51	(0.39–0.63)	<0.001	1580	0.61	(0.49–0.74)	<0.001
1935–1944	2125	0.74	(0.61–0.86)	<0.001	720	0.66	(0.53–0.79)	<0.001
1945–1954	17 838	0.66	(0.54–0.79)	<0.001	1095	0.57	(0.42–0.73)	<0.001
1955–1964	7223	0.59	(0.46–0.72)	<0.001	250	0.48	(0.28–0.68)	<0.001
1965–1969	133	0.59	(0.37–0.80)	<0.001	140	0.55	(0.32–0.79)	<0.001

Linear mixed-effect models with random effects at the survey level, adjusted for smoking status, pack-years, education, lung diseases and respiratory symptoms. Birth cohort reference category = 1894–1904. Z-scores calculated according to Global Lung Function Initiative (GLI-2012) equations.