Table 2.
Results from multiple multilevel regression analyses with FCE test performances as dependent variables are given; unstandardized regression coefficients and their standard errors (b(SE)), and model’s deviance (− 2 * LogLikelihood) by the addition of random and fixed effects are shown
| Floor-to-waist lifta (n = 294) | Six minute walkb (n = 224) | Right handgrip strengthc (n = 335) | Left handgrip strengthc (n = 336) | |||||
|---|---|---|---|---|---|---|---|---|
| b (SE) | Deviance | b (SE) | Deviance | b (SE) | Deviance | b (SE) | Deviance | |
| Null model | 2213.26 | 2878.28 | 2847.88 | 2826.82 | ||||
| Random effects | 2193.04*** | 2867.71** | 2806.11*** | 2787.86*** | ||||
| Clinician and measurement country | ||||||||
| Fixed effectsd | 1941.21*** | 2643.19*** | 2590.43*** | 2597.43*** | ||||
| Intercept | − 2.01 (9.86) | 219.87 (130.89) | − 3.67 (18.00) | − 18.96 (17.39) | ||||
| Age (years) | − 0.16 (0.06) | − 0.13 (0.05) | ||||||
| Sex | ||||||||
| Female | − 4.97 (1.01) | − 11.33 (1.82) | − 11.38 (1.77) | |||||
| Height (cm) | 0.17 (0.05) | 1.98 (0.67) | 0.34 (0.10) | 0.38 (0.09) | ||||
| BMI (kg/m2) | − 3.82 (1.16) | |||||||
| Affected body area | ||||||||
| Lower extremity | − 0.33 (2.01) | |||||||
| Upper extremity | − 8.19 (2.32) | |||||||
| Neck | − 5.94 (2.02) | |||||||
| Generalized | − 5.62 (1.82) | |||||||
| Other | 9.17 (8.30) | |||||||
| Observed physical effort | ||||||||
| Heavy | 7.74 (1.28) | |||||||
| Maximum | 9.04 (1.70) | |||||||
| Test ended prematurely | ||||||||
| Yes | − 4.87 (1.19) | − 168.60 (24.50) | ||||||
| Post-test HR (bpm) | 1.99 (0.30) | |||||||
| Reported pain intensity (NRS) | − 0.64 (0.21) | − 10.89 (2.81) | − 0.77 (0.33) | − 0.91 (0.28) | ||||
| Reported effort during FCE test (Borg CR-10) | − 0.61 (0.20) | − 20.49 (2.79) | ||||||
| Reported social isolation | − 0.34 (0.17) | |||||||
| Reported catastrophizing | − 0.61 (0.27) | |||||||
| Reported disability (PDI) | − 0.07 (0.04) | |||||||
| Physical work demands (DOT) | ||||||||
| Light | 0.65 (2.38) | 0.93 (2.31) | ||||||
| Medium | − 0.06 (2.24) | 0.78 (2.19) | ||||||
| Heavy | 6.77 (2.51) | 6.26 (2.43) | ||||||
| Very heavy | 2.66 (2.86) | 5.65 (2.77) | ||||||
| Days off work | ||||||||
| Less than ¼ year | 3.57 (22.30) | |||||||
| ¼–½ year | − 59.66 (22.75) | |||||||
| ½–1 year | − 12.31 (22.18) | |||||||
| 1–2 years | − 27.40 (25.08) | |||||||
| More than 2 years | − 89.19 (24.17) | |||||||
Reference category: patient’s affected body area: low back; observed physical effort by clinicians: light to moderate; patient’s physical work demands: sedentary; patient’s days off work: no days off
BMI Body Mass Index, HR heart-rate, NRS Numeric Rating Scale, PDI Pain Disability Index, DOT Dictionary of Occupational Titles, FCE Functional Capacity Evaluation
Significance: * < 0.05; ** < 0.01; *** < 0.001
aMeasured in kg
bMeasured in m
cMeasured in kgF
dEach of the fixed effects factors showed a significant improvement of the model at its addition