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. 2021 Jan 6;11(1):e038707. doi: 10.1136/bmjopen-2020-038707

Table 2.

Regression coefficients in multivariable linear mixed models for the EQ-5D utility score and the EQ-VAS and ORs in multivariable logistic mixed models for the dimensions of health status

During the first 2 years after injury
Linear regression coefficients (95% CI) ORs (95% CI)
EQ-5D utility EQ-VAS Mobility Self-care Usual activities Pain/discomfort Anxiety/ depression Cognition
Female sex −0.03 (−0.04 to −0.01)* −1.43 (−2.30 to −0.55)* 1.08 (0.91 to 1.29) 1.08 (0.95 to 1.22) 1.51 (1.32 to 1.72)* 1.56 (1.35 to 1.80)* 2.02 (1.62 to 2.51)* 2.01 (1.54 to 2.63)*
Age (years)
 18–24 Ref Ref Ref Ref Ref Ref Ref Ref
 25–44 0.01 (−0.03 to 0.04) −0.32 (−2.87 to 2.24) 1.13 (0.70 to 1.83) 0.88 (0.61 to 1.28) 1.18 (0.82 to 1.71) 1.08 (0.72 to 1.61) 0.97 (0.53 to 1.77) 0.84 (0.41 to 1.72)
 45–64 0.05 (0.02 to 0.09)* 1.22 (-1.15 to 3.60) 1.20 (0.76 to 1.87) 0.79 (0.56 to 1.13) 0.89 (0.63 to 1.26) 0.81 (0.55 to 1.18) 0.37 (0.21 to 0.66)* 0.37 (0.19 to 0.73)*
 65–74 0.12 (0.08 to 0.16)* 6.43 (3.76 to 9.10)* 0.84 (0.51 to 1.38) 0.55 (0.38 to 0.82)* 0.53 (0.36 to 0.78)* 0.51 (0.33 to 0.78)* 0.10 (0.05 to 0.20)* 0.14 (0.07 to 0.31)*
 ≥75 0.09 (0.05 to 0.13)* 4.98 (2.22 to 7.73)* 1.39 (0.82 to 2.33) 0.98 (0.66 to 1.46) 0.64 (0.43 to 0.96)* 0.45 (0.29 to 0.70)* 0.13 (0.07 to 0.26)* 0.42 (0.19 to 0.92)*
No of comorbidities
 0 Ref Ref Ref Ref Ref Ref Ref Ref
 1 −0.03 (−0.04 to −0.01)* −2.72 (−3.79 to −1.65)* 1.45 (1.18 to 1.77)* 1.19 (1.03 to 1.39)* 1.29 (1.11 to 1.51)* 1.23 (1.04 to 1.46)* 1.65 (1.27 to 2.15)* 1.36 (0.99 to 1.88)
 ≥2 −0.05 (−0.07 to −0.04)* −4.08 (−5.30 to −2.87)* 2.13 (1.69 to 2.68)* 1.62 (1.38 to 1.91)* 1.84 (1.54 to 2.20)* 1.80 (1.47 to 2.20)* 2.34 (1.74 to 3.13)* 2.01 (1.40 to 2.87)*
Injury Severity Score† −0.01 (−0.02 to 0.00)* −0.93 (−1.53 to −0.33)* 1.10 (0.98 to 1.23) 1 (0.92 to 1.09) 1.08 (0.99 to 1.18) 0.92 (0.83 to 1.01) 1.12 (0.97 to 1.30) 1.27 (1.05 to 1.52)*
Length of stay at hospital (days)
 1–2 Ref Ref Ref Ref Ref Ref Ref Ref
 3–7 −0.05 (−0.07 to −0.03)* −3.40 (−4.52 to −2.29)* 2.14 (1.73 to 2.64)* 1.56 (1.33 to 1.84)* 1.72 (1.47 to 2.03)* 1.69 (1.40 to 2.04)* 1.69 (1.27 to 2.25)* 1.15 (0.81 to 1.62)
 8–14 −0.10 (−0.12 to −0.08)* −6.24 (−7.70 to −4.77)* 3.21 (2.39 to 4.29)* 2.60 (2.12 to 3.19)* 2.67 (2.13 to 3.35)* 2.15 (1.68 to 2.75)* 2.73 (1.90 to 3.92)* 1.77 (1.13 to 2.76)*
 ≥15 −0.15 (−0.18 to −0.12)* −9.32 (−11.43 to −7.22)* 6.07 (3.80 to 9.69)* 3.42 (2.51 to 4.66)* 3.97 (2.77 to 5.71)* 2.43 (1.66 to 3.55)* 4.15 (2.48 to 6.95)* 2.81 (1.47 to 5.37)*
Functional Capacity Index
 1 (worse state) −0.07 (−0.15 to 0.00)* −0.89 (−6.27 to 4.48) 1.51 (0.57 to 4.06) 1.79 (0.87 to 3.71) 1.14 (0.51 to 2.54) 1.00 (0.42 to 2.41) 1.46 (0.41 to 5.19) 1.63 (0.31 to 8.57)
 2 −0.06 (−0.10 to −0.03)* −1.22 (−3.57 to 1.12) 1.89 (1.19 to 3.01)* 1.94 (1.42 to 2.66)* 1.59 (1.12 to 2.27)* 1.28 (0.87 to 1.89) 1.57 (0.89 to 2.77) 0.67 (0.32 to 1.38)
 3 −0.03 (−0.07 to 0.00)* −0.48 (−2.84 to 1.89) 2.11 (1.34 to 3.31)* 1.47 (1.08 to 2.02)* 1.88 (1.32 to 2.68)* 1.14 (0.78 to 1.66) 1.10 (0.62 to 1.95) 0.91 (0.44 to 1.86)
 4 −0.03 (−0.05 to −0.01)* −0.04 (−1.50 to 1.43) 1.62 (1.22 to 2.15)* 1.57 (1.29 to 1.93)* 1.42 (1.14 to 1.77)* 1.28 (1.01 to 1.63)* 1.03 (0.72 to 1.48) 0.57 (0.36 to 0.91)*
 5 (best possible state)‡ Ref Ref Ref Ref Ref Ref Ref Ref
Injury classification§
Lower extremity injury
 Pelvic injury −0.04 (−0.07 to −0.02)* −1.64 (−3.37 to 0.10) 2.74 (1.96 to 3.83)* 1.29 (1.02 to 1.64)* 0.97 (0.74 to 1.25) 1.33 (0.99 to 1.78) 0.67 (0.43 to 1.04) 0.57 (0.33 to 0.98)*
 Hip fracture −0.01 (−0.04 to 0.02) −0.34 (−2.20 to 1.52) 2.62 (1.82 to 3.79)* 1.28 (0.99 to 1.66) 1.05 (0.79 to 1.40) 1.04 (0.76 to 1.41) 0.90 (0.57 to 1.42) 1.00 (0.57 to 1.77)
 Tibia, complex foot or femur fracture −0.05 (−0.07 to −0.02)* −1.14 (−2.75 to 0.48) 6.85 (4.97 to 9.44)* 1.27 (1.02 to 1.58)* 1.71 (1.33 to 2.18)* 1.34 (1.03 to 1.76)* 0.8 (0.53 to 1.19) 0.71 (0.43 to 1.18)
Upper extremity injury
 Shoulder and upper arm injury −0.03 (−0.06 to −0.01)* −2.00 (−3.44 to −0.55)* 0.56 (0.42 to 0.74)* 2.22 (1.82 to 2.71)* 1.58 (1.28 to 1.96)* 2.05 (1.60 to 2.61)* 1.01 (0.70 to 1.44) 0.71 (0.46 to 1.12)
 Radius, ulna or hand fracture −0.02 (−0.04 to 0.00)* −0.59 (−2.31 to 1.12) 0.42 (0.30 to 0.58)* 1.46 (1.16 to 1.85)* 1.22 (0.95 to 1.57) 1.23 (0.93 to 1.63) 1.44 (0.94 to 2.19) 0.87 (0.51 to 1.48)
Traumatic brain injury
 Head injury with AIS <2 0.02 (0.01 to 0.04)* 0.64 (−0.41 to 1.70) 0.78 (0.64 to 0.96)* 0.57 (0.49 to 0.67)* 0.77 (0.66 to 0.90)* 0.85 (0.72 to 1.01) 1.15 (0.88 to 1.49) 2.91 (2.12 to 4.01)*
 Head injury with AIS >3 0.04 (0.00 to 0.08)* 2.07 (−0.66 to 4.80) 0.86 (0.51 to 1.43) 0.92 (0.62 to 1.37) 0.78 (0.52 to 1.17) 0.90 (0.58 to 1.39) 1.20 (0.62 to 2.34) 3.29 (1.45 to 7.49)*
Facial injury 0.02 (0.00 to 0.05)* 0.78 (−1.15 to 2.70) 0.52 (0.35 to 0.75)* 0.75 (0.56 to 1.00)* 0.67 (0.51 to 0.89)* 0.67 (0.49 to 0.91)* 1.10 (0.68 to 1.78) 1.21 (0.68 to 2.16)
Thoracic injury 0.06 (0.03 to 0.10)* 3.11 (0.77 to 5.46)* 0.54 (0.35 to 0.84)* 0.56 (0.40 to 0.78)* 0.55 (0.40 to 0.78)* 0.68 (0.47 to 1.00)* 0.58 (0.32 to 1.05) 0.60 (0.29 to 1.24)
Rib fracture −0.01 (-0.03 to 0.01) −0.07 (−1.61 to 1.48) 1.07 (0.80 to 1.43) 1.02 (0.81 to 1.27) 0.93 (0.74 to 1.16) 1.63 (1.26 to 2.11)* 0.96 (0.65 to 1.41) 0.85 (0.53 to 1.36)
Abdominal injury 0.02 (−0.02 to 0.06) 1.68 (−1.27 to 4.63) 0.63 (0.36 to 1.09) 0.57 (0.36 to 0.88)* 0.67 (0.44 to 1.02) 0.56 (0.35 to 0.90)* 0.93 (0.45 to 1.95) 1.55 (0.65 to 3.69)
Spine injury
 Spinal cord injury −0.06 (−0.16 to 0.04) −3.03 (−9.85 to 3.80) 1.86 (0.53 to 6.60) 1.33 (0.53 to 3.33) 1.35 (0.47 to 3.88) 11.61 (2.86 to 47.17)* 0.92 (0.18 to 4.71) 0.30 (0.04 to 2.35)
 Stable vertebral fracture or disc injury −0.06 (−0.08 to −0.03)* −4.16 (−5.99 to −2.33)* 1.31 (0.93 to 1.84) 1.67 (1.30 to 2.15)* 1.79 (1.37 to 2.34)* 2.45 (1.79 to 3.35)* 1.14 (0.72 to 1.79) 0.82 (0.47 to 1.42)
Admission to intensive care unit 0.00 (−0.02 to 0.03) −0.47 (−2.35 to 1.41) 0.81 (0.56 to 1.18) 1.01 (0.77 to 1.32) 1.04 (0.78 to 1.38) 1.08 (0.79 to 1.49) 0.77 (0.48 to 1.23) 2.22 (1.26 to 3.91)*
Pre-injury work status 0.00 (−0.02 to 0.02) −0.23 (−1.62 to 1.17) 0.73 (0.57 to 0.95)* 0.94 (0.78 to 1.14) 1.01 (0.83 to 1.23) 1.12 (0.90 to 1.40) 0.74 (0.53 to 1.04) 0.92 (0.61 to 1.39)
Educational level
 Low‡ Ref Ref Ref Ref Ref Ref Ref Ref
 Middle 0.00 (−0.01 to 0.02) 0.39 (−0.66 to 1.43) 0.94 (0.77 to 1.15) 0.96 (0.83 to 1.11) 0.93 (0.80 to 1.08) 1.07 (0.90 to 1.26) 0.71 (0.55 to 0.92)* 1.05 (0.77 to 1.45)
 High 0.02 (0.00 to 0.03)* 0.36 (−0.76 to 1.49) 0.91 (0.73 to 1.13) 0.99 (0.84 to 1.15) 0.75 (0.64 to 0.89)* 0.82 (0.68 to 0.98)* 0.64 (0.48 to 0.86)* 1.06 (0.75 to 1.51)
Frailty −0.09 (−0.11 to −0.07)* −5.12 (−6.54 to −3.71)* 2.38 (1.75 to 3.24)* 1.79 (1.46 to 2.20)* 2.07 (1.63 to 2.62)* 1.48 (1.18 to 1.87)* 4.94 (3.55 to 6.86)* 4.37 (2.89 to 6.61)*
Pre-injury status¶ 0.49 (0.45 to 0.53)* 0.47 (0.44 to 0.50)*
 No problems‡ Ref Ref Ref Ref Ref Ref
 Moderate/severe problems 13.58 (10.62 to 17.36)* 20.02 (15.50 to 25.86)* 6.39 (5.20 to 7.86)* 6.12 (5.09 to 7.36)* 30.22 (21.62 to 42.25)* 371.77 (224.34 to 616.10)*

*P value of ≤0.05.

†Regression coefficients and ORs (95% CI) represent a four-unit increase on the Injury Severity Score.

‡Reference category.

§Regression coefficients and ORs (95% CI) for patients suffering the injury compared with patients not having the injury.

¶Regression coefficients (95% CI) for pre-injury EQ-5D utility score and the pre-injury EQ-VAS for EQ-5D utility score and EQ-VAS, respectively. ORs (95% CI) for pre-injury moderate and severe problems on the dimensions of the EQ-5D questionnaire (pre-injury mobility, self-care, pain/discomfort, anxiety/depression and cognition, respectively, for the columns).

AIS, Abbreviated Injury Scale; EQ-5D, EuroQol-5-dimensions-3-levels; EQ-VAS, EuroQol Visual Analogue Scale; Ref, reference.