| Age (y)
a
|
44 (28-59) |
43 (28-59) |
46 (27-59) |
<.01 |
| Female
b
|
47 (45-50) |
45 (42-48) |
55 (49-60 |
<.01 |
| Low back pain + leg pain above knee
b
|
87 (84-88) |
90 (88-92) |
69 (62-75) |
<.001 |
| Leg pain below knee + nerve root involvement
b
|
13 (12-16) |
10 (8-12) |
31 (25-38) |
| Nerve root involvement, no
b
|
96 (95-97) |
98 (97-99) |
89 (83-92) |
<.001 |
| Nerve root involvement, yes
b
|
4 (3-5) |
2 (1-3) |
11 (8-17) |
| General health, 75% best
b
|
72 (70-75) |
77 (74-79) |
59 (53-64) |
<.001 |
| General health, 25% worst
b
|
28 (25-30) |
23 (21-26) |
41 (36-47) |
| Expectations, 75% highest
b
|
73 (71-76) |
79 (77-82) |
55 (49-61) |
<.001 |
| Expectations, 25% lowest
b
|
27 (24-29) |
21 (18-23) |
45 (39-51) |
| Duration of pain < 2 wk
b
|
57 (54-59) |
62 (59-66) |
39 (33-44) |
<.001 |
| Duration of pain ≥ 2 wk
b
|
43 (41-46) |
38 (34-41) |
61 (56-67) |
| Previous episodes 0-3
b
|
48 (45-51) |
51 (48-55) |
38 (32-44) |
<.001 |
| Previous episodes > 3
b
|
52 (49-55) |
49 (45-52) |
62 (56-67) |
| Not depressed
b
|
85 (83-87) |
89 (87-91) |
72 (67-77) |
<.001 |
| Depressed
b
|
15 (13-17) |
11 (9-13) |
28 (23-33) |
| No musculoskeletal comorbidity
b
|
83 (81-85) |
88 (86-90) |
64 (58-70) |
<.001 |
| Musculoskeletal comorbidity
b
|
17 (15-19) |
12 (10-14) |
36 (30-42) |
| Low back pain intensity (numeric rating scale 0-10)
a
|
7 (4-9) |
7 (3-9) |
7 (4-9) |
>.01 |
| Activity limitation (Roland-Morris Disability Questionnaire, proportional score 0-100)
a
|
57 (17-83) |
52 (17-83) |
61 (22-87) |
<.001 |