Table 1 Patient-reported baseline characteristics
Local LBP only | LBP + pain above knee | LBP + pain below knee | LBP + signs of nerve root involvement | p-values | |
|---|---|---|---|---|---|
For test of any differences across all subgroups | |||||
Females, (95% CI) | 50% (44–56) | 60% (54–67) | 61% (56–67) | 54% (50–57) | 0.01 |
Age in years, median (IQR) | 47 (36–58) | 45 (36–56) | 52 (40–66) | 50 (38–62) | <0.001 |
Duration in months, median (IQR) | 16 (6–57) | 14 (6–38) | 12 (5–47) | 7 (3–26) | <0.001 |
Previous episodes, (95% CI) | 69% (64–75) | 77% (71–83) | 74% (69–79) | 79% (76–81) | 0.02 |
Pain irritability, (95% CI) | 61% (55–68) | 73% (66–80) | 69% (63–74) | 76% (73–80) | <0.001 |
LBP intensity, median (IQR) | 5 (4–7) | 6 (4–7) | 6 (4–7) | 6 (5–8) | <0.001 |
Leg pain intensity, median (IQR) | 0 | 4 (3–6) | 6 (4–7) | 6 (5–8) | <0.001 (local LBP not in test) |
Activity limitation, median (IQR) | 48 (26–66) | 57 (39–73) | 61 (43–74) | 70 (57–83) | <0.001 |
Any sick leave days in last 3 months*, (95% CI) | 42% (34–51) | 48% (37–59) | 46% (37–55) | 55% (50–60) | 0.04 |
Depressive symptoms, (95% CI) | 12% (8–16) | 17% (12–22) | 13% (10–17) | 20% (18–23) | 0.002 |
Fear of movement, (95% CI) | 21% (16–26) | 24% (18–29) | 20% (16–24) | 26% (23–29) | 0.09 |
General health, mean (SD) | 56 (24) | 53 (22) | 50 (23) | 50 (23) | <0.001 |