Measures
Disease severity and demographic characteristics.
A demographic information form was developed
for this study, including the variables of age, gender, cohabitation, and education. Disease severity was measured during hospitalization by the pulmonary-
function test of FEV1 percent predicted (ie, forced expiratory volume produced in the first second compared with the predicted normal value based on age, height, and gender).27 The chief physician at the Pulmonary Department provided information regarding the main diagnoses and lung function values of each patient.