Model for Developing a Health-Related Quality of Life Questionnaire for Chronic Obstructive Pulmonary Disease

Table 5

Regression variables.

Variable	Value	Standard error	t-ratio	Prob (t)
A	−0.1482	2.7698	−5.351	0.0
B	−5.8662	0.0194	−0.301	0.0341
C	−4.4479	2.6682	−1.666	0.098
D	2.3828	1.1024	2.161	0.032
E	0.1752	1.5025	11.660	0.0
F	3.5046	6.8791	50.945	0.0

A, variable regression for x1, smoking habit; B, variable regression for x2, value of FVC; C, variable regression for x3, value of FEV1; D, variable regression for x4, value of PEF; E, variable regression for x5, exacerbation frequency; t-ratio, ratio of the estimated parameter and standard deviation of the same; Prob (t), probability that the value of the regression coefficient with the independent variable is 0.