TABLE 4.

Calculation of effect sizes relative to the effect size of SARA

Metric	Slope	Standard error of slope	Relative Cohen’s da
Cervical spinal cord, level C3	−0.53	0.08	0.81
Cervical spinal cord, level C2	−0.43	0.08	0.68
Medulla oblongata	−24.50	4.55	0.61
Pons	−210.01	23.11	1.03
Midbrain	−72.76	8.46	0.97
Cerebellum white matter	−226.05	68.67	0.35
Cerebellum, anterior lobe	−39.51	16.78	0.26
Cerebellum crus II	−104.17	33.15	0.35
Cerebellum X	−5.93	1.50	0.45
Pallidum	−35.86	4.17	0.97

Linear models with the estimated disease duration were the basis for the estimated slope of all respective metrics as well as for the SARA sum score. As a measure of effect size, we calculated Cohen’s d values for a presumed 50% reduction of the decrease of SARA and each MRI metric.

^aCohen’s d is given in relation to SARA: relative Cohen’s d = Cohen’s d of the metric/Cohen’s d of SARA.