Table 5.

Descriptive statistics for the five MFI-20 scales by subgroups

	All	CFS-like	Chronically Unwell	Well
General Fatigue
Mean	12.90	16.38	12.84	8.42
SD	4.68	2.73	3.93	3.59
25%	9.00	15.00	10.00	6.00
Median	14.00	17.00	13.00	8.00
75%	17.00	18.00	16.00	11.00
Range	4-20	6-20	4-20	4-20
% at floor	3.45	0	1.49	10.31
% at ceiling	6.13	13.01	3.36	0.45
Physical Fatigue
Mean	10.85	13.63	10.39	7.77
SD	4.36	3.79	3.76	3.36
25%	7.00	11.00	8.00	5.00
Median	11.00	14.00	10.00	7.00
75%	14.00	16.00	13.00	10.00
Range	4-20	4-20	4-20	4-19
% at floor	6.39	0.34	5.60	15.25
% at ceiling	2.81	6.51	1.12	0
Reduced Activity
Mean	9.25	11.32	9.06	6.76
SD	4.16	4.37	3.75	2.67
25%	6.00	8.00	6.00	5.00
Median	8.00	11.00	8.00	6.00
75%	12.00	15.00	12.00	8.00
Range	4-20	4-20	4-20	4-16
% at floor	11.49	3.77	8.96	24.66
% at ceiling	2.43	5.14	1.49	0
Reduced Motivation
Mean	9.58	11.95	9.29	6.82
SD	3.90	3.53	3.35	2.91
25%	6.00	9.50	7.00	4.00
Median	9.00	12.00	9.00	6.00
75%	12.00	14.00	11.00	8.00
Range	4-20	4-20	4-20	4-20
% at floor	11.49	1.37	10.07	26.46
% at ceiling	0.77	1.37	0.37	0.45
Mental Fatigue
Mean	10.95	13.77	10.98	7.23
SD	4.54	3.77	4.00	3.07
25%	7.00	11.50	8.00	4.00
Median	11.00	14.00	11.00	7.00
75%	14.00	17.00	14.00	9.00
Range	4-20	4-20	4-20	4-20
% at floor	9.96	1.37	6.34	25.56
% at ceiling	3.70	7.19	2.61	0.45