Cox regression analysis of do-not-resuscitate (DNR) order implementation#

Hazard ratio (95% CI)p-value
No DNRRef.
DNR 04.984 (2.121–11.71)<0.0001
DNR 1a4.217 (2.597–6.845)<0.0001
DNR 1b8.699 (5.860–42.91)<0.0001
DNR 2/310.36 (6.808–15.79)<0.0001
Age years1.030 (1.013–1.047)0.001
FEV1 % pred0.986 (0.978–0.995)0.002
MRCQ score 3–5 versus 1–21.494 (1.095–2.038)0.011
Chronic oxygen dependency? Yes versus no1.024 (0.714–1.467)0.899
Previous mechanical ventilation? Yes versus no1.101 (0.676–1.792)0.699

Bold type represents statistical significance. #: adjusted for age, forced expiratory volume in 1 s (FEV1), Medical Research Council Questionnaire (MRCQ) score, chronic respiratory dependency and previous need for mechanical ventilation. ref.: reference against which other DNR values are compared.