Table 5.
Multivariate analyses of the relationships between cognitive measures as dependent variables and group allocation (chronic fatigue group vs HC), depression symptoms (MFQ), anxiety traits (STAI-T) and sleep problems (KSQ) as independent variables
| Dependent variable | Regression | Independent variables | B (95% CI) | β Coefficient | p Value | R2 |
|---|---|---|---|---|---|---|
| Processing speed | Multivariate 1 | Group | 2.9 (0.4 to 5.4) | 0.201 | 0.022 | 0.06 |
| MFQ | −0.04 (−0.1 to 0.06) | −0.075 | 0.392 | |||
| Multivariate 2 | Group | 2.9 (0.3 to 5.4) | 0.200 | 0.027 | 0.06 | |
| STAI-T | −0.04 (−0.2 to 0.07) | −0.069 | 0.443 | |||
| Multivariate 3 | Group | 3.5 (0.8 to 6.2) | 0.246 | 0.011 | 0.06 | |
| KSQ | −0.1 (−1.2 to 0.9) | −0.023 | 0.807 | |||
| Working memory | Multivariate 1 | Group | −1.9 (−3.3 to −0.4) | −0.220 | 0.011 | 0.10 |
| MFQ | 0.05 (−0.01 to 0.1) | 0.154 | 0.072 | |||
| Multivariate 2 | Group | −1.9 (−3.4 to −0.4) | −0.225 | 0.012 | 0.09 | |
| STAI-T | 0.05 (−0.02 to 0.1) | 0.125 | 0.157 | |||
| Multivariate 3 | Group | −1.5 (−3.0 to 0.1) | −0.171 | 0.067 | 0.11 | |
| KSQ | −0.7 (−1.3 to −0.06) | −0.202 | 0.031 | |||
| CWIT cognitive inhibition (time) | Multivariate 1 | Group | 5.7 (−0.4 to 11.8) | 0.164 | 0.065 | 0.03 |
| MFQ | −0.05 (−0.3 to 0.2) | −0.034 | 0.701 | |||
| Multivariate 2 | Group | 5.6 (−0.6 to 11.9) | 0.161 | 0.079 | 0.03 | |
| STAI-T | −0.06 (−0.3 to 0.2) | −0.036 | 0.696 | |||
| Multivariate 3 | Group | 5.7 (−1.0 to 12.4) | 0.164 | 0.092 | 0.03 | |
| KSQ | 0.3 (−2.2 to 2.9) | 0.025 | 0.797 | |||
| HVLT-R verbal learning | Multivariate 1 | Group | −1.6 (−3.2 to 0.05) | −0.169 | 0.057 | 0.03 |
| MFQ | 0.01 (−0.05 to 0.08) | 0.032 | 0.717 | |||
| Multivariate 2 | Group | −1.8 (−3.5 to −0.13) | −0.194 | 0.034 | 0.03 | |
| STAI-T | −0.01 (−0.09 to 0.07) | −0.025 | 0.784 | |||
| Multivariate 3 | Group | −1.9 (−3.7 to −0.15) | −0.207 | 0.034 | 0.04 | |
| KSQ | 0.16 (−0.5 to 0.85) | 0.044 | 0.649 | |||
| BRIEF global executive composite | Multivariate 1 | Group | 8.6 (4.9 to 12.5) | 0.360 | <0.001 | 0.23 |
| MFQ | −0.2 (−0.35 to −0.04) | −0.199 | 0.014 | |||
| Multivariate 2 | Group | 7.6 (3.8 to 11.5) | 0.318 | <0.001 | 0.25 | |
| STAI-T | −0.3 (−0.46 to −0.1) | −0.266 | 0.001 | |||
| Multivariate 3 | Group | 7.6 (3.4 to 11.8) | 0.315 | <0.001 | 0.23 | |
| KSQ | 2.1 (0.5 to 3.7) | 0.229 | 0.010 |
BRIEF, Behaviour Rating Inventory of Executive Function; CWIT, Color Word Interference Test; HC, healthy controls; KSQ, Karolinska Sleep Questionnaire; MFQ, Mood and Feelings Questionnaire; STAI-T, Spielberger State-Trait Inventory.