Skip to main content

Table 1 Characteristics of clinically evaluated subjects

From: An evaluation of exclusionary medical/psychiatric conditions in the definition of chronic fatigue syndrome

Characteristics

  

Exclusionary Condition

Odds ratio (OR)*

 

All

Yes

No

Unadjusted Ors

Adjusted Ors

 

n = 781

n = 280 (36%)

n = 501 (64%)

(95% CI) †

(95% CI)

Part A

Classification

        

   CFS-like

291

(37.26)

141

(48.45)

150

(51.55)

3.25 (2.03-4.80)

1.50 (0.79-2.87)

   Unwell

267

(34.19)

89

(34.19)

178

(66.67)

1.73 (1.15-2.59)

0.89 (0.53-1.52)

   Well

223

(28.55)

50

(22.42)

173

(77.58)

1.00

1.00

Age (years), mean (SD)

43.50

(10.36)

43.10

(10.39)

43.73

(10.35)

0.94 (0.81-1.09)

0.83 (0.70-1.00)

Sex

        

   Male

186

(23.82)

71

(38.17)

115

(61.83)

1.14 (0.81-1.60)

1.44 (0.96-2.16)

   Female

595

(76.18)

209

(35.13)

386

(64.87)

1.00

1.00

Race

        

   Black

195

(24.97)

91

(46.67)

104

(53.33)

1.86 (1.34-2.60)

1.89 (1.24-2.88)

   Other

35

(4.48)

13

(37.14)

22

(62.86)

1.26 (0.62-2.56)

1.12 (0.51-2.45)

   White

551

(70.55)

176

(31.94)

375

(68.06)

1.00

1.00

Residential areas

        

   Rural

383

(49.04)

144

(37.60)

239

(62.40)

1.81 (1.16-2.82)

2.02 (1.20-3.39)

   Urban

266

(34.06)

103

(38.72)

163

(61.18)

1.90 (1.19-3.02)

1.96 (1.16-3.29)

   Metropolitan

132

(16.90)

33

(25.00)

99

(75.00)

1.00

1.00

BMI (kg/m2), mean (SD)

28.08

(5.34)

28.76

(5.52)

27.70

(5.20)

1.22 (1.05-1.41)

1.02 (0.86-1.22)

Part B

MFI

      

Per SD increment

Per SD increment

   General fatigue

12.90

(4.69)

14.10

(4.36)

12.22

(4.74)

1.52 (1.30-1.78)

1.23 (0.87-1.74)

   Physical fatigue

10.86

(4.37)

12.05

(4.32)

10.20

(4.25)

1.54 (1.32-1.79)

1.06 (0.78-1.44)

   Reduced activity

9.24

(4.16)

10.13

(4.33)

8.75

(3.98)

1.39 (1.20-1.61)

0.93 (0.72-1.19)

   Reduced motivation

9.58

(3.90)

10.60

(4.12)

9.01

(3.66)

1.51 (1.30-1.76)

1.21 (0.92-1.59)

   Mental fatigue

10.94

(4.54)

12.09

(4.50)

10.29

(4.43)

1.50 (1.29-1.74)

1.12 (0.89-1.40)

SF-36

      

Per SD increment

Per SD increment

   Physical Functioning

75.64

(24.03)

67.57

(26.41)

80.11

(21.35)

1.68 (1.44-1.95)

0.62 (0.34-1.10)

   Role physical

41.41

(41.60)

27.14

(37.45)

49.50

(41.68)

1.78 (1.52-2.09)

0.70 (0.50-0.99)

   Bodily pain

60.61

(26.63)

52.35

(26.93)

65.23

(25.34)

1.65 (1.41-1.92)

0.66 (0.41-1.07)

   Social functioning

71.32

(27.78)

62.28

(29.17)

76.37

(25.65)

1.67 (1.43-1.94)

1.08 (0.70-1.68)

   Mental health

68.50

(22.23)

62.29

(23.05)

71.98

(20.99)

1.55 (1.33-1.80)

1.11 (0.63-1.94)

   Role emotional

49.12

(43.31)

37.74

(41.49)

55.49

(43.05)

1.52 (1.31-1.77)

1.08 (0.78-1.50)

   Vitality

47.77

(28.01)

41.39

(27.03)

51.38

(27.94)

1.44 (1.24-1.67)

1.61 (1.02-2.53)

   General health

61.87

(23.57)

55.24

(23.88)

65.58

(22.58)

1.56 (1.34-1.82)

0.98 (0.64-1.52)

   PCS

46.28

(10.72)

43.07

(11.64)

48.08

(9.72)

1.60 (1.38-1.86)

1.50 (0.40-5.68)

   MCS

44.67

(12.79)

41.27

(13.63)

46.58

(11.89)

1.52 (1.31-1.76)

0.68 (0.22-2.07)

   HUI2†

76.14

(14.61)

70.75

(14.80)

79.16

(13.61)

1.82 (1.56-2.13)

Not included§

SI

      

Per SD increment

Per SD increment

   SI_CFS

23.13

(20.58)

28.13

(21.45)

20.34

(19.56)

1.45 (1.25-1.68)

0.78 (0.56-1.08)

   SI_NCFS

19.89

(18.09)

24.44

(20.21)

17.34

(16.26)

1.48 (1.27-1.71)

1.04 (0.79-1.37)

  1. *Adjusted ORs were obtained for the multiple logistic regression models including all variables in the entire table; ORs with P-values < 0.05 are in bold font.
  2. † Nichole's Health Utility Index 2 (HUI2) was included in the multivariate model because it is a linear combination of eight of the Medical Outcomes Survey Short Form-36 (SF-36) subscales and strongly correlated with physical component summary (PCS) and mental component summary (MCS).
  3. CFS = chronic fatigue syndrome; CI = confidence interval; SD = standard deviation; BMI = body mass index; MFI = multidimensional fatigue inventory; SI_CFS = symptom inventory summary score of 8 CFS symptoms; SI_NCFS = symptom inventory summary score of non-CFS symptoms
Back to article page

BMC Medicine

ISSN: 1741-7015

Contact us