Table 3 Univariate analysis of oxygen use and potential confounders for survival

0.59 (0.39–0.88)

0.011

0.58 (0.36–0.92)

0.021

0.99 (0.97–1.00)

0.16

0.99 (0.98–1.01)

0.50

1.33 (0.93–1.91)

0.12

1.25 (0.83–1.89)

0.28

0.99 (0.98–1.00)

0.008

0.98 (0.97–0.99)

0.002

1.00 (0.99–1.01)

0.94

1.01 (1.00–1.02)

0.24

1.02 (0.98–1.06)

0.28

1.02 (0.98–1.07)

0.27

2.26 (1.57–3.24)

<  0.001

2.81 (1.86–4.24)

<  0.001

0.83 (0.57–1.20)

0.32

0.98 (0.64–1.49)

0.92

1.09 (0.76–1.55)

0.64

1.14 (0.76–1.71)

0.51

0.48 (0.36–0.62)

<  0.001

0.31 (0.22–0.43)

<  0.001

1.68 (1.29–2.18)

<  0.001

2.14 (1.59–2.87)

<  0.001

0.44 (0.25–0.80)

0.006

0.46 (0.23–0.91)

0.026

0.76 (0.51–1.14)

0.18

0.73 (0.45–1.17)

0.19