Table 4.

Multivariable Linear Regression for Exacerbation Frequency

GOLD	Classic CB			SGRQ CB			SGRQ vs Classic
	β Coeffa	SE	P Value	β Coeffa	SE	P Value	P Value
All	0.083	0.030	.006	0.166	0.026	< .0001	.017
0	0.031	0.035	.366	0.059	0.029	.039	.391
1, 2	0.134	0.045	.003	0.193	0.040	< .0001	.239
3, 4	0.096	0.095	.312	0.310	0.088	< .0001	.038

Probability values in boldface indicate significance. Coeff = coefficient. See Table 1 legend for expansion of other abbreviations.

^aAge, race, sex, pack-year history, current smoking, oxygen use, modified Medical Research Council dyspnea score, % emphysema, prior exacerbation frequency, FEV₁% predicted, 6-min walk distance, and BMI as covariates.