Table 2.
Comparisons of LM CSA, pain intensity, functional disability, and QOL among the study groups based on ITT.
| Outcome | Treatment group Mean (SD) |
Adjusted between-group differences Mean (95% CI) |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| LSERUSI-biofeedback | LSEno-biofeedback | Min intervention | LSERUSI-biofeedback vs LSEno-biofeedback |
Cohen’s d | LSERUSI-biofeedback vs Min intervention |
Cohen’s d | LSEno-biofeedback vs Min intervention |
Cohen’s d | p-value† | |
| LM CSA | < 0.001 | |||||||||
| Baseline | 5.63 (1.43) | 5.57 (1.16) | 5.94 (1.29) | – | – | – | ||||
| 8 weeks | 6.95 (1.74) | 6.14 (0.93) | 5.25 (1.33) | 0.81 (0.00 to 1.62)* | 0.58 | 1.79 (0.91 to 2.65)*** | 1.10 | 0.98 (0.13 to 1.82)* | 0.78 | |
| 20 weeks | 6.98 (1.77) | 5.37 (0.94) | 4.41 (0.49) | 1.61 (0.79 to 2.42)*** | 1.14 | 2.66 (1.79 to 2.53)*** | 1.98 | 1.06 (0.21 to 1.95)** | 1.28 | |
| NPRS (0–10) | < 0.001 | |||||||||
| Baseline | 6.76 (0.72) | 6.66 (0.60) | 6.76 (0.72) | – | – | – | ||||
| 8 weeks | 2.73 (1.63) | 2.23 (0.77) | 6.23 (0.67) | 0.50 (− 0.01 to 1.10) | 0.39 | − 3.56 (− 4.01 to − 2.98)*** | 2.81 | − 4.00 (− 4.51 to − 3.45)*** | 5.54 | |
| 20 weeks | 2.86 (1.61) | 3.16 (0.87) | 6.16 (0.79) | − 0.30 (− 0.81 to 0.21) | 0.23 | − 3.30 (− 3.81 to − 2.78)*** | 2.65 | − 3.00 (− 3.51 to − 2.48)*** | 3.61 | |
| RMDQ (0–24) | < 0.001 | |||||||||
| Baseline | 13.7 (1.88) | 12.9 (2.68) | 12.5 (2.27) | – | – | – | ||||
| 8 weeks | 5.33 (2.53) | 5.00 (1.25) | 12.4 (1.35) | 0.33 (− 0.71 to 1.37) | 0.17 | − 7.10 (− 8.14 to − 6.05)*** | 3.49 | − 7.43 (− 8.47 to − 6.38)*** | 5.69 | |
| 20 weeks | 4.40 (2.90) | 4.93 (1.14) | 12.1 (1.55) | − 0.53 (− 1.57 to 0.51) | 0.24 | − 7.77 (− 8.81 to − 6.72)*** | 3.31 | − 7.23 (− 8.27 to − 6.18)*** | 5.27 | |
| PCS-12 (0–100) | < 0.001 | |||||||||
| Baseline | 30.1 (5.12) | 30.3 (4.71) | 29.9 (5.20) | – | – | – | ||||
| 8 weeks | 46.7 (7.66) | 47.4 (4.50) | 27.3 (4.34) | − 0.68 (− 3.72 to 2.34) | 0.11 | 19.3 (16.2 to 22.3)*** | 3.11 | 20.0 (16.9 to 23.0)*** | 4.55 | |
| 20 weeks | 44.3 (6.69) | 49.2 (5.04) | 34.1 (8.73) | − 4.89 (− 7.92 to − 1.86)* | 0.83 | 10.2 (7.20 to 13.2)*** | 1.31 | 15.1 (12.1 to 18.1)*** | 2.12 | |
| MCS-12 (0–100) | < 0.001 | |||||||||
| Baseline | 39.7 (3.83) | 40.7 (7.12) | 43.8 (4.90) | – | – | – | ||||
| 8 weeks | 56.3 (7.56) | 52.7 (3.59) | 33.1 (6.78) | 3.63 (0.32 to 6.94)* | 0.61 | 23.2 (19.9 to 26.5)*** | 3.23 | 19.6 (16.2 to 22.9)*** | 3.62 | |
| 20 weeks | 56.4 (7.56) | 49.0 (4.63) | 33.2 (9.78) | 7.34 (4.03 to 10.6)*** | 1.18 | 23.1 (19.8 to 26.4)*** | 2.65 | 15.8 (12.5 to 19.1)*** | 2.07 | |
CI, confidence interval; LSE, lumbar stabilization exercise; Min, minimal; BMI, body mass index; CSA, cross-sectional area; LM, lumbar multifidus; NPRS, Numerical Pain Rating Scale; RMDQ, Rolland-Morris disability questionnaire; PCS, physical component summary; MCS, mental component summary.
Higher scores in LMM CSA, PCS-12 and MCS-12 indicate better improvement.
Lower scores in NPRS and RMDQ indicate better improvement.
Participants in LSERUSI-biofeedback group = 30, LSEno-biofeedback group = 30, and minimal intervention group = 30.
*Comparison is significant at the 0.05 level,
**Comparison is significant at the 0.01 level.
***Comparison is significant at the 0.001 level.
†p-value for interaction effect.