Table 4 Baseline characteristics by each follow-up population
From: Back beliefs in patients with low back pain: a primary care cohort study
Variable | Baseline study population n = 2293 | 3-month non-responders n = 786 | 3-month study population N = 1230 | 12-month non-responders N = 377 | 12-month study population N = 429 |
|---|---|---|---|---|---|
Age in years, mean (SD) | 44(14) | 40(13) | 47(13) | 41(14) | 46(13) |
Age range in years | 18–87 | 18–80 | 18–80 | 18–80 | 18–80 |
Females | 41% | 38% | 43% | 41% | 43% |
Episodes of LBP before current one, | |||||
None | 17% | 19% | 16% | 23% | 20% |
1 episode | 14% | 13% | 14% | 19% | 12% |
2–3 episodes | 24% | 25% | 24% | 20% | 24% |
> 3 episodes | 45% | 43% | 46% | 39% | 45% |
Total (n) | 1613 | 344 | 1067 | 203 | 379 |
Time since start of current episode of LBP, | |||||
1–14 days | 60% | 61% | 61% | 61% | 61% |
2–4 weeks | 11% | 10% | 11% | 9% | 10% |
1–12 months | 18% | 19% | 18% | 19% | 20% |
> a year | 10% | 11% | 10% | 11% | 9% |
Total (n) | 2279 | 778 | 1221 | 375 | 425 |
Days with LBP during the previous year | |||||
Less than or equal to 30 days | 63% | 60% | 65% | 63% | 64% |
> 30 days | 37% | 40% | 35% | 37% | 36% |
Total (n) | 2293 | 350 | 1230 | 210 | 375 |
Back pain (VAS 0–10), mean | 6.7 | 6.7 | 6.7 | 6.8 | 6.6 |
Disability (RMDQ 0–23), mean | 12.7 | 11.9 | 12.8 | 12.2 | 12.3 |