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 variableRegressionIndependent variablesB (95% CI)β Coefficientp ValueR2
Processing speedMultivariate 1Group2.9 (0.4 to 5.4)0.2010.0220.06
MFQ−0.04 (−0.1 to 0.06)−0.0750.392
Multivariate 2Group2.9 (0.3 to 5.4)0.2000.0270.06
STAI-T−0.04 (−0.2 to 0.07)−0.0690.443
Multivariate 3Group3.5 (0.8 to 6.2)0.2460.0110.06
KSQ−0.1 (−1.2 to 0.9)−0.0230.807
Working memoryMultivariate 1Group−1.9 (−3.3 to −0.4)−0.2200.0110.10
MFQ0.05 (−0.01 to 0.1)0.1540.072
Multivariate 2Group−1.9 (−3.4 to −0.4)−0.2250.0120.09
STAI-T0.05 (−0.02 to 0.1)0.1250.157
Multivariate 3Group−1.5 (−3.0 to 0.1)−0.1710.0670.11
KSQ−0.7 (−1.3 to −0.06)−0.2020.031
CWIT cognitive inhibition (time)Multivariate 1Group5.7 (−0.4 to 11.8)0.1640.0650.03
MFQ−0.05 (−0.3 to 0.2)−0.0340.701
Multivariate 2Group5.6 (−0.6 to 11.9)0.1610.0790.03
STAI-T−0.06 (−0.3 to 0.2)−0.0360.696
Multivariate 3Group5.7 (−1.0 to 12.4)0.1640.0920.03
KSQ0.3 (−2.2 to 2.9)0.0250.797
HVLT-R verbal learningMultivariate 1Group−1.6 (−3.2 to 0.05)−0.1690.0570.03
MFQ0.01 (−0.05 to 0.08)0.0320.717
Multivariate 2Group−1.8 (−3.5 to −0.13)−0.1940.0340.03
STAI-T−0.01 (−0.09 to 0.07)−0.0250.784
Multivariate 3Group−1.9 (−3.7 to −0.15)−0.2070.0340.04
KSQ0.16 (−0.5 to 0.85)0.0440.649
BRIEF global executive compositeMultivariate 1Group8.6 (4.9 to 12.5)0.360<0.0010.23
MFQ−0.2 (−0.35 to −0.04)−0.1990.014
Multivariate 2Group7.6 (3.8 to 11.5)0.318<0.0010.25
STAI-T−0.3 (−0.46 to −0.1)−0.2660.001
Multivariate 3Group7.6 (3.4 to 11.8)0.315<0.0010.23
KSQ2.1 (0.5 to 3.7)0.2290.010
  • 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.