Table 1 Categorical risk factors for LBP lasting seven or more consecutive days after one year of follow-up (LBP at t1) in univariate analyses.
Asymptomatic workers | Mildly symptomatic workers | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
LBP at t1 | LBP at t1 | ||||||||||
n | % | RR | 95%CI | P-value | n | % | RR | 95%CI | P-value | ||
Current LPB (reported before the physical examination) | No | 354 | 9.6 | / | / | / | 331 | 14.8 | 1.00 | 0.013 | |
Yes | / | / | 4 | 75.0 | 5.07 | (2.72 – 9.44) | |||||
Iliac crest height inequality ≥ 1.5 cm | No | 336 | 9.5 | 1.00 | 0.673 | 320 | 15.6 | 1.00 | 0.700 | ||
Yes | 17 | 11.8 | 1.23 | (0.32 – 4.74) | 12 | 8.3 | 0.53 | (0.08 – 3.54) | |||
Scoliosis | No | 299 | 10.0 | 1.00 | 0.523 | 289 | 16.3 | 1.00 | 0.375 | ||
Yes | 55 | 7.3 | 0.72 | (0.27 – 1.98) | 45 | 11.1 | 0.68 | (0.29 – 1.63) | |||
Lumbar flexion: Pain in the low back or buttock | No | 343 | 9.6 | / | / | 1.000 | 330 | 15.5 | 1.00 | 0.400 | |
Yes | 8 | 0.0 | 3 | 33.3 | 2.16 | (0.43 – 10.90) | |||||
Lumbar extension: Pain in the low back | No | 333 | 9.6 | / | / | 0.608 | 305 | 13.4 | 1.00 | 0.008 | |
Yes | 10 | 0.0 | 26 | 34.6 | 2.58 | (1.41 – 4.69) | |||||
Pain in the low back or buttock in lateral flexion | No | 349 | 9.7 | / | / | 1.000 | 325 | 14.5 | 1.00 | 0.010 | |
Yes | 2 | 0.0 | 10 | 50.0 | 3.46 | (1.76 – 6.80) | |||||
Pain in the low back or buttock-thigh or knee- other places in SLR | No | 99 | 9.1 | 1.00 | 0.838 | 118 | 16.9 | 1.00 | 0.595 | ||
Yes | 255 | 9.8 | 1.08 | (0.52 – 2.23) | 217 | 14.7 | 0.87 | (0.52 – 1.45) | |||
Neurological examination of the lower limbs | Normal | 345 | 9.3 | 1.00 | 0.548 | 327 | 15.6 | 1.00 | 1.000 | ||
Abnormal | 8 | 12.5 | 1.35 | (0.21 – 8.70) | 8 | 12.5 | 0.80 | (0.13 – 5.10) | |||
Body mass index (kg/m2) | Normal | 233 | 8.6 | 1.00 | 0.026 | 235 | 14.5 | 1.00 | 0.359 | ||
Overweight | 65 | 6.2 | 0.72 | (0.25 – 2.02) | 64 | 21.9 | 1.51 | (0.87 – 2.64) | |||
(≥ 25 and <30) | |||||||||||
Obese (>30) | 31 | 22.6 | 2.63 | (1.21 – 5.71) | 18 | 16.7 | 1.15 | (0.39 – 3.39) | |||