Prognostic factors at baseline for percentage change in the Roland Morris disability questionnaire (RMDQ) (n=115)
| Spearman’s rank correlation Correlation with percentage change in RMDQ | Forward stepwise multivariate linear regression* Independent variables p<0.20 entered in the model, adjusted for age No significant association | ||||
| N | r | p Value | β (95% CI) | p Value | |
| Age, years | 115 | −0.11 | 0.23 | −0.0017 (−0.014 to 0.011) | 0.79 |
| Lifestyle behavioural factors | |||||
| Body mass index (kg/m2) | 114 | −0.13 | 0.18 | ||
| Smoker (n=72)—non-smoker (n=48) | 115 | −0.072 | 0.44 | ||
| AUDIT-C (0–12)† | 113 | 0.11 | 0.23 | ||
| Sleep quantity (1–4)‡ | 115 | 0.18 | 0.054 | ||
| Sleep quality (1–4)§ | 113 | 0.16 | 0.099 | ||
| SCI-93¶ | 115 | −0.17 | 0.075 | ||
| LTPAI (hours per week)** | 115 | 0.13 | 0.18 | ||
| Body function | |||||
| Pain localisations (0–18)†† | 115 | −0.15 | 0.10 | ||
| Pain intensity 10 mm (VAS 0-100)‡‡ | 115 | 0.078 | 0.41 | ||
| Fatigue 10 mm (VAS 0-100)‡‡ | 115 | −0.046 | 0.62 | ||
| 6MWT, 100 m | 113 | 0.17 | 0.065 | ||
| Hand grip strength 50 (N) | 115 | 0.057 | 0.55 | ||
| HADS-A (0–21) §§ | 115 | −0.023 | 0.81 | ||
| HADS-D (0–21)§§ | 115 | −0.11 | 0.24 | ||
| Participation | |||||
| Work ability (n=95)—no work ability (n=25) | 115 | 0.15 | 0.11 | ||
| Environmental factors | |||||
| Private social support (4–20)¶¶ | 115 | 0.14 | 0.14 | ||
| Health-related quality of life | |||||
| PCS (0–100)*** | 114 | 0.029 | 0.76 | ||
| MCS (0–100)*** | 114 | 0.14 | 0.13 | ||
*Percentage change in RMDQ as dependent variable. The final model was adjusted for age using standard (Enter) multivariate linear regression.
†The AUDIT-C, three items. Higher scores reflect higher alcohol consumption (0–12).
‡One item: ‘Do you think you get enough sleep?’. Higher scores indicate better sleep (1–4).
§One item: ‘On the whole, how do you think you sleep?’. Higher scores indicate better sleep (1–4).
¶Higher scores indicate more severe clinical stress symptoms (0–140).
**The LTPAI assesses the total hours of physical activity in leisure time during a typical week.
††Self-reported pain locations registered by a figure with predefined body locations (0–18).
‡‡Perceived pain intensity, fatigue over the last week rated on a VAS (0–100). Higher values indicate more pain, fatigue.
§§Higher scores indicate more anxiety (0–21) and depression (0–21).
¶¶Medical Outcome Study Social Support Survey (four-item scale) reflects private social support ranging from 1 to 5. Higher scores reflect more perceived support (4–20).
***SF-36. The PCS score (0–100) and MCS score (0–100).
6MWT, 6 min walk test; AUDIT-C, Alcohol Use Disorders Identification Test; HADS-A and HADS-D, Hospital Anxiety and Depression Scale; LTPAI, leisure time physical activity instrument; MCS, mental component summary; PCS, physical component summary; SCI-93, Stress and Crisis Inventory; SF-36, short-form health survey; VAS, visual analogue scale.