Table 3

Results from the random effects model for predicting forced expiratory volume in one second (FEV₁), with asthma categories combined (any asthma). Data from the Tucson Epidemiological Study of Airways Obstructive Disease

Variables	Coefficient	se	p‐value
Anthropometric and smoking factors
Sex	1.311	0.037	<0.0001
Height	0.044	0.002	<0.0001
Pack-yrs of smoking	−0.0062	0.0004	<0.0001
Age yr	−0.0009	0.0012	0.455
Disease main effects
Any asthma	−0.255	0.054	<0.0001
COPD	−0.0996	0.066	0.131^#
Disease effects on rate of decline in FEV₁
Asthma by age	−0.0036	0.0009	<0.0001
COPD by age	−0.0028	0.0011	0.015
COPD by sex by age²	−0.00006	0.00001	<0.0001
Interactions and nonlinear factors
Interactions with sex
Age by sex	−0.010	0.0006	<0.0001
Nonlinear factors
Age²	−0.00018	0.00001	<0.0001

COPD: chronic obstructive pulmonary disease
^#: results not statistically significant at the α=0.05 level