Predictors of exoskeleton motor learning in spinal cord injured patients

Figures & data

Table 1. Personal and injury characteristics.

	Completed training program (N = 20)
Sex (male/female)	12/8
Age (years), mean (SD)	37 ± 10
Post-injury (years), mean (SD)	8 ± 8
Age at injury onset (years), mean (SD)	29 ± 10
Neurological level of SCI (Thoracic), mean (SD)	8 ± 3
AIS^a (A/B)	19/1
BMI^b, mean (SD)	23 ± 3
Sport (hours per week), mean (SD)	3 ± 2
Active lifestyle^c (times per week), mean (SD)^e	5 ± 6
Anxiety (HADS^d sub score), mean (SD)	4 ± 3

^a AIS: American Spinal Injury Association Impairment Scale.

^b BMI: body mass index.

^c met the Dutch physical activity guidelines.

^d HADS: Hospital Anxiety and Depression Scale.

^e N = 19.

Figure 1. Explained variance (Pearson’s correlation R²) at Intermediate-skills-test 1, 2, and 3 for the 9 predictors. An R² above .20 is significant (p < 0.05), N = 20.

Figure 2. Scatterplot for the predictors with a significant correlation with exoskeleton skill performance (p < 0.05) at Intermediate-skills-test 1, 2, and 3.

Table 2. Multiple forward stepwise regression.

	Variable 1	Variable 2	Variable 3	Model R^2	Model p value	Formula
Intermediate-skills-test 1	Lesion level (β = 0.59, p = 0.002)	Anxiety (β = 0.45, p = 0.009)	Active lifestyle (β = 0.34, p = 0.040)	0.65	0.001	Performance = 1.20 (lesion level)+0.94 (anxiety)+0.45 (active lifestyle) – 8.76
Intermediate-skills-test 2	Lesion level (β = 0.55, p = 0.012)			0.30	0.012	Performance = 1.12 (lesion level)+0.88
Intermediate-skills-test 3	BMI (β=–0.36, p = 0.031)	Active lifestyle (β = 0.51, p = 0.003)	Age (β=–0.47, p = 0.008)	0.66	0.001	Performance=–1.05 (BMI)+0.84 (active lifestyle)  – 0.39 (age)+48.86

Figure 3. Explained variance (Pearson’s correlation R²) of the average achieved final skills for the 9 predictors.