Table 4.
Tobit regression model of Factors associated with overall SF-6D utility score
| Factor | Coefficient | 95% CI | P-value |
|---|---|---|---|
| Sociodemographic | |||
| Age in yeara | −0.001 | (− 0.002,0.001) | 0.289 |
| Male | 0.037 | (0.006,0.069) | 0.019 |
| Education (University or above) | |||
| Primary or below | 0.022 | (−0.012,0.057) | 0.206 |
| Middle School | 0.037 | (0.002,0.073) | 0.039 |
| High School | 0.039 | (0.002,0.075) | 0.037 |
| Occupation (Others) | |||
| Retired | −0.006 | (−0.035,0.022) | 0.665 |
| Working | 0.018 | (−0.007,0.042) | 0.153 |
| Current smoker | −0.006 | (−0.023,0.012) | 0.516 |
| Years since first smoking | −0.001 | (−0.002,0.001) | 0.348 |
| Cigarettes per day (Heavy) | |||
| Light | 0.013 | (−0.009,0.034) | 0.257 |
| Moderate | 0.001 | (−0.017,0.019) | 0.936 |
| Clinical | |||
| Underweight or normal, BMI < 23 kg/m2 | −0.003 | (−0.021,0.014) | 0.718 |
| Number of chronic diseases | 0.004 | (−0.006,0.014) | 0.450 |
| Pulmonary Symptoms in BCSS scorea | − 0.018 | (−0.025,-0.011) | < 0.001 |
| Airway obstruction | 0.010 | (−0.013,0.032) | 0.393 |
BMI body mass index, BCSS Breathlessness, Cough, and Sputum Scale, COPD chronic obstructive pulmonary disease, CI confidence interval
aNegative coefficients indicated the increase in one unit of independent variable was associated with decrease in SF-6D score