Correlation between self-management, psychological cognitive impairment, and quality of life in elderly chronic obstructive pulmonary disease patients

Table 6 Assignments for the variables included in the generalized linear model

Factor	Variable	Assignment
Degree of education	X1	1 = “Elementary school and below”, 2 = “Junior high school and vocational school, high school and vocational college”, 3 = “College, undergraduate and above”
Engage in intellectual activities every day	X2	1 = Yes, 2 = No
Frequency of physical exercise	X3	1 = “0 time/week”, 2 = “Approximately 1 time/week”, 3 = “≥ 3 times/week”
Sleep duration per night	X4	1 = “≤ 6 hours”, 2 = “> 6 hours”
Course of disease	X5	1 = “< 5 years”, 2 = “5-10 years”, 3 = “> 10 years”
Fall history in the past year	X6	0 = None, 1 = Yes
Coexistence of multiple illnesses	X7	0 = None, 1 = Yes
Pulmonary function classification	X8	1 = “Level I”, 2 = “Level II”, 3 = “Level III”, 4 = “Level IV”
Dyspnea classification	X9	0 = “Level 0”, 1 = “Level 1”, 2 = “Level 2”, 3 = “Level 3”, 4 = “Level 4”
Hypoxemia	X10	0 = None, 1 = Yes
Persist in using inhaled medication	X11	0 = None, 1 = Yes
Long-term oxygen therapy	X12	0 = None, 1 = Yes
The number of acute attacks in the past year	X13	Continuous variable, no assignment required
Total score of self-management	X14	Continuous variable, no assignment required
Cognitive decline	X15	0 = Did not occur, 1 = Occurred
Total score of quality of life	Y	Continuous variable, no assignment required