Table 2 Baseline characteristics of randomised participants by compliance status; complier, non-complier or control
| Ā | Advice plus cognitive behavioural intervention (nā=ā468) | ||||
|---|---|---|---|---|---|
| Ā | Control | Complier | Non-complier | Mean difference* | p valueā |
| Ā | (nā=ā233) | (nā=ā294) | (nā=ā174) | (95% CI) | Ā |
Age (years) | 54.1 (14.9) | 55.0 (14.3) | 50.5 (14.8) | 4.5 (1.8, 7.2) | 0.001 |
Sex | Ā | Ā | Ā | - | 0.694 |
āFemale | 142 (60.9%) | 173 (58.8%) | 105 (60.3%) | Ā | Ā |
āMale | 90 (38.6%) | 121 (41.2%) | 68 (39.1%) | ||
āMissing | 1 (0.4%) | 0 | 1 (0.6%) | ||
Ethnic origin | - | 0.258 | |||
āWhite | 206 (88.4%) | 268 (91.2%) | 144 (82.8%) | Ā | Ā |
āMixed | 3 (1.3%) | 2 (0.7%) | 2 (1.1%) | ||
āAsian | 8 (3.4%) | 9 (3.1%) | 12 (6.9%) | ||
āBlack | 4 (1.7%) | 4 (1.4%) | 3 (1.7%) | ||
āChinese | 1 (0.4%) | 1 (0.3%) | 0 | ||
āMissing | 11 (4.7%) | 10 (3.4%) | 13 (7.5%) | ||
Severity of back pain | Ā | Ā | Ā | - | 0.802 |
āModerately troublesome | 130 (55.8%) | 157 (53.4%) | 95 (54.6%) | Ā | Ā |
āVery or extremely troublesome | 103 (44.2%) | 137 (46.6%) | 79 (45.4%) | Ā | |
Age left full-time education (years) | - | 0.584 | |||
āā¤16 | 121 (51.9%) | 168 (57.1%) | 98 (56.3%) | Ā | Ā |
ā17-19 | 61 (26.2%) | 65 (22.1%) | 39 (22.4%) | Ā | |
āā„20 | 49 (17.2%) | 48 (16.3%) | 25 (14.4%) | Ā | |
āStill in full-time education | 2 (0.9%) | 0 | 1 (0.6%) | Ā | |
āMissing | 9 (3.9%) | 13 (4.4%) | 11 (6.3%) | Ā | |
In employmentā | - | 0.612 | |||
āYes | 110 (47.2%) | 147 (50.0%) | 91 (52.3%) | Ā | Ā |
āNo | 122 (52.4%) | 146 (49.7%) | 82 (47.1%) | Ā | Ā |
āRetired | 77 (63.1%) | 94 (64.4%) | 36 (43.9%) | Ā | Ā |
āAt home not looking for work | 4 (3.3%) | 12 (8.2%) | 13 (15.9%) | Ā | |
āUnable to work because of back pain | 11 (9.0%) | 12 (8.2%) | 10 (12.2%) | Ā | |
āUnable to work because of other illness | 9 (7.4%) | 10 (6.8%) | 6 (7.3%) | Ā | |
āUnemployed and looking for work | 8 (6.6%) | 1 (0.7%) | 3 (3.7%) | Ā | |
āIn full-time education | 2 (1.6%) | 0 | 0 | Ā | |
āOther | 3 (2.5%) | 1 (0.7%) | 5 (6.1%) | Ā | |
āReason not given | 8 (6.6%) | 16 (11.0%) | 9 (11.0%) | Ā | |
Duration of back pain (years since first onset) | 13.2 (12.7) | 14.1 (14.2) | 11.4 (11.2) | 2.8 (0.2, 5.3) | 0.034 |
Frequency of back pain (past 6 weeks) | - | 0.009 | |||
āEveryday | 162 (69.5%) | 189 (64.3%) | 126 (72.4%) | Ā | Ā |
āLess often than everyday | 47 (20.2%) | 82 (27.9%) | 29 (16.7%) | ||
āMissing | 24 (10.3%) | 23 (7.8%) | 19 (10.9%) | ||
Roland Morris questionnaire | 8.5 (4.7) | 8.6 (4.9) | 9.1 (5.2) | -0.4 (-1.4, 0.5) | 0.357 |
Modified Von Korff disability | 46.2 (23.8) | 47.0 (23.6) | 51.0 (24.1) | -4.0 (-8.6, 0.5) | 0.083 |
Modified Von Korff pain | 59.4 (19.5) | 57.6 (19.3) | 62.2 (18.9) | -4.6 (-8.2, -1.0) | 0.014 |
EQ-5D | 0.6 (0.3) | 0.6 (0.3) | 0.5 (0.3) | 0.1 (-0.01, 0.1) | 0.082 |