Table 1.
Baseline characteristics of general practitioners and patients. Values are numbers (percentages) unless stated otherwise
| Characteristic | Minimal intervention strategy | Usual care |
|---|---|---|
| General practitioners | (n=28) | (n=32) |
| Mean (SD) age (years)* | 43.0 (7.2) | 45.7 (7.4) |
| Women | 6 (21) | 12 (38) |
| No of included patients/general practitioner: | ||
| 0 | 1 (4) | 5 (16) |
| 1-5 | 17 (61) | 14 (44) |
| >5 | 10 (36) | 13 (41) |
| Patients | (n=143) | (n=171) |
| Demographic characteristics: | ||
| Mean (SD) age (years) | 43.4 (11.1) | 42.0 (12.0) |
| Women | 68 (48) | 81 (47) |
| Dutch nationality | 139 (97) | 167 (98) |
| Public health insurance | 101 (71) | 116 (68) |
| Educational level and work status: | ||
| Education level* | ||
| primary or below | 50 (35) | 56 (33) |
| secondary | 66 (46) | 89 (53) |
| college, university | 27 (19) | 24 (14) |
| Paid job | 117 (82) | 139 (81) |
| Disability payment because of LBP | 3 (2) | 3 (2) |
| Characteristics of LBP: | ||
| Median (interquartile range) duration of current episode (days) | 11 (5-21) | 14 (7-21) |
| Frequency of LBP episodes in previous year: | ||
| 1-2 episodes | 83 (58) | 104 (61) |
| ≥3 episodes | 28 (20) | 32 (19) |
| exacerbation of persisting LBP | 32 (22) | 35 (21) |
| Pain radiating below knee* | 18 (13) | 25 (15) |
| Primary measures: | ||
| Mean (SD) functional disability score (RDQ, 0-24) | 11.7 (5.4) | 12.2 (5.0) |
| Sick leave because of LBP* (among the working population) | 40 (35) | 57 (41) |
| Secondary measures: | ||
| Mean (SD) pain severity during day (0-10)† | 4.9 (2.0) | 4.8 (2.0) |
| Mean (SD) severity of main complaint (0-10)* | 7.0 (1.9) | 6.8 (2.0) |
| Mean (SD) perceived general health (SF-36, 1-5)* | 2.7 (0.8) | 2.8 (0.8) |
| Psychosocial measures: | ||
| Mean (SD) fear-avoidance beliefs (FABQ, 0-24) | 14.3 (5.6) | 15.3 (5.2) |
| Mean (SD) catastrophising thoughts (CSQ, 0-36) | 10.3 (6.6) | 11.2 (6.9) |
| Mean (SD) distress (4DSQ, 0-32)† | 8.3 (7.0) | 9.5 (7.3) |
LBP=low back pain.
RDQ= Roland-Morris disability questionnaire; SF-36=short form 36; FABQ=fear-avoidance beliefs questionnaire; CSQ=coping strategies questionnaire; 4DSQ=four dimensional symptom questionnaire (higher scores mean more functional disability, worse health, more fear-avoidance, more catastrophising, or more distress).
*
n=2 missing.
†
n=1 missing.