Table 1.
Patient characteristics: All values show the mean and standard deviation for each individual group
| SABP | SABPp | SABPr | CBP | HC | Missings | |
|---|---|---|---|---|---|---|
| N | 48 | 21 | 27 | 29 | 29 | NA |
| Age | 35.0 (13.4) | 36.6 (13.9) | 33.8 (13.0) | 38.7 (15.8) | 35.7 (14.7) | 0/0/0/0/0 |
| Gender (m/f) | 18/30 | 6/15 | 12/15 | 16/13 | 17/12 | 0/0/0/0/0 |
| Number of days with pain during last year | 66.2 (42.9) | 57.6 (32.6) | 73.0 (49.1) | 241 (92.3) | NA | 7/3/4/2/NA |
| Time since first pain episode (months)a | 25.2 [4.3, 119.9] | 28.5 [4.4, 100.6] | 21.8 [6.1, 119.9] | 62.5 [18.8–145.3] | NA | 0/0/0/0/NA |
| Delta pain severity (FU-BL): absolute | −0.91 (1.19) | 0.05 (0.69) | −1.65 (0.93) | NA | NA | 0/0/0/NA/NA |
| Delta pain severity (FU-BL): percentage | −25.7 (35.9) | 3.4 (20.4) | −48.3 (28.1) | NA | NA | 0/0/0/NA/NA |
| Pain severity (MPI) | 2.33 (0.93) | 2.42 (0.92) | 2.27 (0.95) | 2.67 (0.85) | NA | 0/0/0/1/NA |
| Interference (MPI) | 1.81 (1.11) | 2.05 (1.17) | 1.63 (1.04) | 2.47 (1.10) | NA | 4/2/2/4/NA |
| Negative mood (MPI) | 2.67 (1.18) | 2.75 (1.16) | 2.61 (1.21) | 2.71 (1.03) | NA | 4/2/2/4/NA |
| Life control (MPI) | 3.92 (1.27) | 3.88 (1.28) | 3.96 (1.28) | 3.92 (1.02) | NA | 4/2/2/4/NA |
| Support (MPI) | 2.17 (1.82) | 2.39 (1.92) | 2.00 (1.76) | 2.72 (1.67) | NA | 6/3/3/4/NA |
| CPGa | 1.00 [0, 2] | 2.00 [0, 2] | 1.00 [0, 2] | 2.00 [0.5, 3.00] | NA | 6/4/2/6/NA |
| ÖMPQ | 72.0 (31.1) | 71.9 (34.1) | 72.1 (29.2) | 82.2 (35.9) | NA | 0/0/0/1/NA |
| Anxiety (HADS) | 7.23 (3.98) | 7.06 (3.93) | 7.36 (4.09) | 7.32 (4.50) | 3.54 (2.39) | 5/3/2/4/3 |
| Depression (HADS) | 4.81 (4.01) | 4.33 (2.83) | 5.16 (4.71) | 5.59 (4.08) | 2.96 (4.24) | 5/3/2/4/3 |
| Perceived stress (PSS) | 18.1 (6.84) | 18.1 (7.19) | 18.0 (6.70) | 17.9 (7.63) | 9.88 (5.76) | 4/2/2/4/5 |
MPI, West Haven-Yale Multidimensional Pain Inventory; CPG, Chronic Pain Grade; ÖMPQ, Örebro Musculoskeletal Pain Questionnaire; HADS, Hospital Anxiety and Depression Scale; HC, healthy control; CBP, chronic back pain; SABP, patients with subacute back pain; SABPp/r, patients with SABP with persistent pain or recovered pain after 6 months, based on a pain reduction of 20% from baseline to the follow-up assessment; FU, follow up after 6 months; BL, baseline assessment; SD, standard deviation.
a
For the Chronic Pain Grade and pain onset, the median and interquartile range are depicted.