Table 1.
Demographics, symptoms, level and grade of slip and life style factors in per-cent (except age and sick-leave period) before treatment according to type of randomised treatment (observed numbers within brackets)
| All (n = 111) | Non-instrumented (N = 40) | Instrumented (n = 37) | Exercise (n = 34) | |
|---|---|---|---|---|
| Mean age (years) | 39 | 39 | 39 | 37 |
| Mean age at onset of symptoms (years) | 26 | 25 | 29 | 25 |
| Women | 49 (54) | 45 (18) | 57 (21) | 44 (15) |
| Men | 51 (57) | 55 (22) | 43 (16) | 56 (19) |
| Low back pain only | 31 (33) | 25 (10) | 30 (11) | 39 (12) |
| Low back pain + sciatica | 62 (67) | 68 (27) | 62 (23) | 55 (17) |
| Sciatica only | 7 (8) | 8 (3) | 8 (3) | 6 (2) |
| Level L5 | 85 (94) | 83 (33) | 84 (31) | 88 (30) |
| Level L4 | 13 (14) | 15 (6) | 14 (5) | 9 (3) |
| Levels L4 and L5 | 3 (3) | 3 (1) | 3 (1) | 3 (1) |
| Grade 1 slip | 60 (67) | 68 (27) | 54 (20) | 59 (20) |
| Grade 2 slip | 38 (42) | 30 (12) | 43 (16) | 41 (14) |
| Grade 3 slip | 2 (2) | 3 (1) | 3 (1) | 0 |
| Sick-leave or disability pension | 71 (79) | 68 (27) | 84 (31) | 62 (21) |
| Mean sick-leave before treatment (months) | 16 | 15 | 14 | 18 |
| Blue collar | 80 (87) | 90 (36) | 75 (27) | 73 (24) |
| Immigrants | 32 (35) | 30 (12) | 27 (10) | 38 (13) |
| Married | 74 (82) | 75 (30) | 76 (28) | 71 (24) |
| Smokers | 54 (60) | 63 (25) | 57 (21) | 41 (14) |
| Medication for other than back pain | 21 (23) | 30 (12) | 16 (6) | 15 (5) |