Hazard ratio for death by Cox’s proportional model.

ICU, Intensive Care Unit; %FEV1, FEV1 predicted; COC, Continuity of Care.a adjusted for age, sex, age, sex, health insurance type, use of home oxygen therapy, Charlson comorbidity index, ICU use, number of hospital admissions, and respiratory impairment grade.b Calculated comorbidity scores; extracted age scores.c Time-dependent covariate; COC index ranged from 0 to 1; 1 means that one patient has visited only one physician.Hazard ratio for death by Cox’s proportional model.