Table 2. Subgroup analyses.

	Unadjusted analysis				Adjusted analysis
Factors	N studies	Pooled HR	Within strata	Between strata comparison	N studies	Pooled HR	Within strata	Between strata comparison
Publication year
Less than 10 y	7	1.77 (1.29 to 2.42)	0.0004		3	1.34 (1.08 to 1.65)	0.0070
10 to 20 y	10	2.29 (1.59 to 3.30)	<0.0001	0.45	9	1.26 (1.09 to 1.46)	0.0020	0.88
More than 20 y	10	2.30 (1.61 to 3.29)	<0.0001		2	1.25 (1.09 to 1.45)	0.0002
Study' continent
America (North)	7	1.83 (1.16 to 2.91)	<0.0001	0.02	5	1.17 (0.96 to 1.43)	0.1300	0.56
Asia/Oceania	6	3.31 (2.44 to 4.49)	<0.0001		2	1.32 (1.13 to 1.53)	0.0003
Europe	15	2.07 (1.75 to 2.45)	<0.0001		7	1.35 (1.11 to 1.65)	0.0020
Population studied
General geriatrics	18	2.06 (1.66 to 2.56)	<0.0001	0.42	9	1.19 (1.07 to 1.32)	0.0010	0.19
Other	9	2.53 (1.62 to 3.97)	<0.0001		5	1.40 (1.12 to 1.75)	0.0030
Setting
Hospital inpatients	8	2.60 (1.92 to 3.52)	<0.0001		2	1.49 (1.20 to 1.86)	0.0003
Community	10	2.07 (1.43 to 3.00)	<0.0001		7	1.23 (1.01 to 1.49)	0.0400
Home care	4	1.94 (1.39 to 2.71)	<0.0001	0.61	1	1.15 (1.06 to 1.25)	0.0008	0.16
Mix	5	2.14 (1.47 to 3.13)	<0.0001		4	1.24 (1.08 to 1.43)	0.0030
Follow-up
<1 y	4	2.38 (1.85 to 3.05)	<0.0001		0	-	-
1–5 y	14	2.21 (1.57 to 3.10)	<0.0001	0.79	10	1.30 (1.09 to 1.55)	0.0040	0.23
>5 y	9	2.06 (1.47 to 2.88)	<0.0001		4	1.16 (1.10 to 1.23)	<0.0001
Design
Prospective	13	2.20 (1.71 to 2.82)	<0.0001	0.68	12	1.26 (1.10 to 1.45)	0.0009	0.85
Retrospective	3	2.05 (1.63 to 2.57)	<0.0001		2	1.31 (0.94 to 1.84)	0.1200
Adjustment level*
Low	-	-	-	-	6	1.31 (1.09 to 1.57)	0.0040	0.54
High	-	-	-		8	1.22 (1.06 to 1.40)	0.0070

* Highly adjusted models are those with adjustment for at least both functional status and neurological deficit.

HR: hazard ratio; NOQ scale: Newcastle-Ottawa Quality Assessment scale; UIC: urinary indwelling catheters; y: years