Table 1 Study population characteristics

n

49

49

NA

40

38

NA

Gender

Female

41

40

NA

32

29

NA

Male

8

9

8

9

Age

All

51.09 ± 11.46

50.89 ± 11.40

p = 0.95

51.16 ± 11.90

51.84 ± 10.92

p = 0.79

Female

50.94 ± 11.39

49.40 ± 11.95

p = 0.59

50.98 ± 11.93

50.08 ± 11.72

p = 0.85

Male

51.85 ± 12.58

57.52 ± 4.82

p = 0.61

51.85 ± 12.58

57.52 ± 4.82

p = 0.61

BMI

All

25.44 ± 4.39

26.63 ± 4.87

p = 0.23

25.56 ± 4.53

27.22 ± 4.70

p = 0.08

Female

25.35 ± 4.62

26.47 ± 5.23

p = 0.38

25.47 ± 4.86

27.17 ± 5.18

p = 0.15

Male

25.92 ± 3.11

27.34 ± 2.86

p = 0.17

25.92 ± 3.11

27.34 ± 2.86

p = 0.17

Type of onset

Acute

NA

79.59%

NA

NA

78.95%

NA

Gradual

NA

20.41%

NA

NA

21.05%

NA

Disease duration

 < 3 years

NA

4

NA

NA

2

NA

 > 3 years

NA

45

NA

NA

36

NA

Season

Fall

48.98%

44.90%

NA

47.50%

42.11%

NA

Summer

51.02%

55.10%

NA

52.50%

57.89%

NA

Site

Miami, FL

18.37%

20.41%

NA

17.50%

15.79%

NA

Salt Lake City, UT

30.61%

28.57%

NA

30.00%

28.95%

NA

Incline Village, NV

22.45%

22.45%

NA

22.50%

23.68%

NA

New York, NY

28.57%

28.57%

NA

30.00%

31.58%

NA

MFI-20

General fatigue

7.61 ± 2.78

17.28 ± 3.70

p < 0.001

7.80 ± 2.80

17.42 ± 3.46

p < 0.001

Physical fatigue

6.71 ± 2.45

16.57 ± 3.54

p < 0.001

6.70 ± 2.38

16.82 ± 3.50

p < 0.001

Reduced activity

6.29 ± 2.47

15.47 ± 4.08

p < 0.001

6.25 ± 2.52

15.76 ± 3.93

p < 0.001

Reduced motivation

6.88 ± 2.45

12.45 ± 4.17

p < 0.001

6.95 ± 2.47

12.50 ± 4.39

p < 0.001

Mental fatigue

7.55 ± 3.29

14.8 ± 4.21

p < 0.001

7.45 ± 3.40

15.03 ± 4.28

p < 0.001

SF-36

Physical component score

55.49 ± 3.64

27.91 ± 9.68

p < 0.001

55.16 ± 3.57

27.67 ± 9.85

p < 0.001

Mental component score

54.02 ± 7.30

40.18 ± 10.74

p < 0.001

54.13 ± 5.23

40.83 ± 10.72

p < 0.001