Table 2.
Simple and partial correlation analyses of clinical scores and magnetic resonance imaging measures.
|
Brain Volume |
Brain Lesion Volume |
Spinal Cord Volume |
Spinal Cord Lesion Volume |
|
|---|---|---|---|---|
| Age, all, simple | −0.1 (0.005*) | 0.4 (3e-12**) | −0.01 (0.8) | 0.09 (0.08) |
| Sex (f > m: <0), all, simple | 0.5 (1e-25**) | 0.1 (0.05) | 0.1 (0.06) | 0.1 (0.03*) |
| Disease Duration, all, simple | −0.2 (4e-04**) | 0.4 (2e-18**) | −0.2 (7e-04**) | 0.3 (1e-06**) |
| Intracranial V, all, simple | 0.9 (6e-185**) | 0.02 (0.7) | 0.4 (2e-13**) | −0.02 (0.7) |
| Scanner | n/a | n/a | (>0.3) | (>0.9) |
| Brain Volume, all, partial-1 | / | −0.5 (6e-26**) | 0.2 (0.002*) | −0.1 (0.007*) |
| Brain Lesion V, all, partial-1 | −0.5 (6e-26**) | / | 0.04 (0.5) | 0.2 (2e-06**) |
| SC Volume, all, partial-1 | 0.2 (0.002*) | 0.04 (0.5) | / | 0.08 (0.1) |
| SC Lesion V, all, partial-1 | −0.1 (0.007*) | 0.2 (2e-06**) | 0.08 (0.1) | / |
| EDSS | ||||
| CIS/RRMS, simple | −0.2 (0.003*) | 0.3 (1e-09**) | −0.07 (0.2) | 0.3 (1e-08**) |
| partial-1 | −0.2 (0.001*) | 0.2 (4e-05**) | −0.06 (0.3) | 0.3 (4e-07**) |
| partial-2 | −0.3 (0.2) | 0.1 (0.03*) | −0.07 (0.2) | 0.2 (2e-05**) |
| PMS, simple | −0.3 (0.1) | 0.4 (0.02*) | −0.07 (0.7) | 0.1 (0.4) |
| partial-1 | −0.02 (0.9) | 0.2 (0.3) | 0.2 (0.2) | 0.1 (0.4) |
| partial-2 | 0.11 (0.9) | 0.16 (0.5) | 0.17 (0.5) | 0.02 (0.9) |
| All, simple | −0.2 (2e-06**) | 0.5 (5e-20**) | −0.2 (7e-04**) | 0.3 (5e-12**) |
| partial-1 | −0.2 (4e-05**) | 0.3 (3e-07**) | −0.08 (0.1) | 0.3 (1e-07**) |
| partial-2 | −0.3 (0.2) | 0.2 (0.004*) | −0.09 (0.06) | 0.2 (9e-06**) |
| Further Clinical Scores (All patients) | ||||
| 25FWalk, simple | −0.2 (0.002*) | 0.2 (0.001*) | −0.3 (3e-05**) | 0.2 (0.001*) |
| partial-1 | −0.2 (0.01*) | 0.1 (0.09) | −0.2 (0.001*) | 0.1 (0.06) |
| partial-2 | −0.4 (0.1) | 0.06 (0.4) | −0.2 (9e-04**) | 0.1 (0.08) |
| 9HPeg, simple | −0.05 (0.4) | 0.2 (2e-04**) | −0.01 (0.8) | 0.3 (8e-06**) |
| partial-1 | −0.1 (0.07) | 0.2 (0.005*) | 0.004 (1.0) | 0.2 (3e-04**) |
| partial-2 | −0.2 (0.5) | 0.1 (0.07) | −0.01 (0.8) | 0.2 (0.001*) |
| Fatigue, simple | −0.1 (0.1) | 0.05 (0.4) | 0.03 (0.6) | 0.1 (0.2) |
Effect sizes (standardized ß) and, in parentheses, p values of simple correlations ('simple') with the four volumes in interest, namely brain white matter lesion volume, brain volume, spinal cord lesion volume, and spinal cord volume are given. Effect sizes (standardized ß) and p values of partial correlations ('partial') are also given for the four volumes and for clinical scores. Partial-1 correlations include one variable of interest, namely one volume or one clinical score, and the control variables of age, sex, disease duration, (total) intracranial volume, and scanner. Partial-2 correlations additionally include the three remaining volumes. Significance is indicated by one/two asterisks (p < 0.05/0.001).
9HPeg, Nine-Hole Peg Test; 25FWalk, 25-Foot Walk Test; All, all patients (CIS/RRMS and PMS); ß, standardized beta; CIS/RRMS, group of patients with clinically isolated syndrome or relapsing-remitting multiple sclerosis; EDSS, Expanded Disability Status Scale; f > m: <0, higher values in women translate into negative ß values; Fatigue, score of Multiple Sclerosis Inventory Cognition; n/a, not applicable; PMS, progressive MS; SC, spinal cord; Scanner, factor variable with 3 levels, number relates to smallest p value; V, volume.