Table 4.

Univariable analysis and the final baseline and baseline plus 6-week follow-up linear multivariable models for the 6 month OMAS score

Variable	Univariable analysis		Final multivariable baseline model		Final multivariable baseline plus 6-week follow-up model
	β coefficient (95% CI)	P value	β coefficient (95% CI)	P value	β coefficient (95% CI)	P value
Baseline
Constant			44.34 (30.04 to 58.64)	<0.001	34.62 (20.00 to 49.23)	<0.001
Preinjury OMAS score	0.48 (0.39 to 0.57)	<0.001	0.22 (0.09 to 0.34)	0.001	0.19 (0.07 to 0.31)	0.002
Alcohol consumed per week (units)	0.34 (0.16 to 0.52)	<0.001	0.14 (−0.03, 0.32)	0.102	0.23 (0.07 to 0.40)	0.007
EQ-5D-3L VAS Score (postinjury)	0.18 (0.10 to 0.25)	<0.001	0.08 (0.003 to 0.15)	0.043
Sex		<0.001		<0.001		0.010
Female	−8.94 (–12.82 to 5.05)		−6.90 (−10.75 to 3.06)		−4.99 (−8.79 to 1.19)
Walking distance*		<0.001		0.002		0.015
>0.5 mile	19.10 (15.01 to 23.19)		7.79 (2.97 to 12.61)		5.90 (1.16 to 10.64)
Walking aid		<0.001		0.003		0.006
Yes	−20.31 (–24.95, to 15.66)		−8.35 (−13.89, to 2.82)		−7.60 (13.01 to 2.20)
Smoking status†		0.185		0.049		0.061
Ex-smoker	−1.57 (−7.87, 4.72)		−3.31 (−8.93, 2.30)		−3.26 (−8.73, 2.20)
Never	1.83 (−4.33, 8.00)		0.85 (−4.69, 6.38)		0.62 (−4.76, 6.00)
Health status‡		<0.001		0.023		0.050
Very good	−4.19 (−8.50, 0.13)		−1.79 (−5.82, 2.24)		−2.25 (−6.17, 1.66)
Good	−13.42 (−18.13 to 8.70)		−6.90, (−11.48 to 2.32)		−6.50 (−10.93 to 2.07)
Fair	−20.69 (−27.41 to 13.97)		−2.97 (−10.32, 4.38)		−4.48 (−11.51, 2.56)
Poor	−23.48 (−44.30to 2.66)		5.94 (−14.25, 26.14)		2.95 (−16.61, 22.51)
Patient age	−0.54 (−0.77 to 0.31)	<0.001
MMSE	1.21 (0.43 to 2.00)	0.003
EQ-5D-3L VAS Score (day before injury)	0.35 (0.25 to 0.46)	<0.001
EQ-5D-3L score (day before injury)	32.3 (23.07 to 41.53)	<0.001
EQ-5D-3L score (postinjury)	11.24 (4.65 to 17.83)	<0.001
Number of comorbidities	−3.58 (−4.89 to 2.28)	<0.001
Fracture pattern		0.175
Weber C	−3.59 (−8.78, 1.60)
Admitted from§		0.441
Warden accommodation	−8.31 (−23.57, 6.96)
Acute hospital	−10.01 (−40.38, 20.37)
Community hospital	9.99 (−20.38, 40.37)
Temporary residence	10.96 (−5.35, 27.26)
Treatment received¶		0.249
ORIF	1.67 (−1.83, 5.18)
Other	−6.33 (−16.75, 4.09)
Home support **		0.003
Live alone or with someone	26.11 (8.63 to 43.59)
Additional 6 week variables
6 week EQ-5D-3L VAS	0.32 (0.21 to 0.42)	<0.001
Readmission to hospital
Yes	−3.30 (−9.49, 2.89)	0.295
Started partial weight bearing		0.575
Yes	−1.01 (−4.54, 2.52)
Radiological malalignment present		0.124				0.025
Yes	−2.78 (−6.33, 0.77)				−3.54 (−6.62 to 0.45)
Range of injured ankle motion Dorsiflexion	0.15 (−0.04, 0.34)	0.131			0.18 (0.007 to 0.35)	0.041
Range of injured ankle motion Plantar flexion	0.14 (0.01 to 0.28)	0.032			0.17 (0.05 to 0.28)	0.006
6 week OMAS	0.33 (0.22 to 0.44)	<0.001			0.19 (0.09 to 0.30)	<0.001
6 week EQ-5D-3L score	25.69 (18.66 to 32.72)	<0.001			10.21 (3.64 to 16.78)	0.002

*Reference category for walking distance is ‘<0.5 mile’.

†Reference category for smoking status is ‘Current smoker’.

‡Reference category for health status is ‘Excellent’.

§Reference category for admitted from is ‘Own home’.

¶Reference category for treatment received is ‘CCC’.

**Reference category for home support is ‘live with care or has external care support’.

NB, EQ-5D-3L VAS Score (postinjury) omitted from final model by backward selection and correlation with 6-week score.

MMSE, Mini-Mental State Examination; OMAS, Olerud and Molander Ankle Scale; ORIF, Open Reduction and Internal Fixation; VAS, Visual Analogue Scale.