Table 2.

Linear mixed models for change in daily functioning over time (unconditional model) and effect of frailty (univariable and multivariable models) (n = 388)

	Unadjusted model		Univariable model		Multivariable model*
	Estimate (SE)	P-value	Estimate (SE)	P-value	Estimate (SE)	P-value
Fixed effects
At admission (intercept)
Daily functioning (Barthel Index; range 0–20)	11.31 (0.81)	<0.001	11.51 (0.46)	<0.001	11.64 (0.31)	<0.001
Frailty (Clinical Frailty Scale; range 1–9)	N/A	N/A	−1.50 (0.13)	<0.001	−0.90 (0.11)	<0.001
Change before admission (slope)
Change per week	−3.05 (0.11)	<0.001	−3.08 (0.11)	<0.001	−3.10 (1.06)	<0.001
Change after admission (slope)
Per month: linear component	2.51 (0.15)	<0.001	2.58 (0.15)	<0.001	2.73 (0.14)	<0.001
Per frailty score: linear component	N/A	N/A	−0.13 (0.09)	0.170	−0.17 (0.09)	0.075
Per month: quadratic component	−0.26 (0.02)	<0.001	−0.28 (0.02)	<0.001	−0.30 (0.02)	<0.001
Per frailty score: quadratic component	N/A	N/A	0.03 (0.01)	0.019	0.04 (0.01)	0.007
	Variance (SD)		Variance (SD)		Variance (SD)
Random effects
At admission (intercept)
Between persons variance	8.13 (2.85)		5.40 (2.32)		1.50 (1.23)
Between countries variance	6.00 (2.45)		1.72 (1.31)		0.70 (0.84)
After admission (slope of change)
Between persons variance	0.03 (0.19)		0.04 (0.20)		0.05 (0.22)
Between countries variance	0.07 (0.26)		0.05 (0.22)		0.01 (0.10)
Residual	10.64 (3.26)		10.52 (3.24)		9.98 (3.16)

N/A, not available.

^*Adjusted for age, sex, premorbid BI, Functional Comorbidity Index, hospital length of stay and ICU stay.