Table 1

Weighted proportion of descriptive characteristics in mutually exclusive categories of fatiguing illness.
Characteristic
 % Non-fatigued n = 444
 % Chronic fatigue n = 338
 % CFS-like n = 49
 % Total
Female
 57
 66
 70
 58
White
 81
 89
 88
 82
Non-Hispanic
 95
 92
 99
 95
Age Group (years)



     18–29
 22
 11
 18
 21
     30–39
 21
 15
 19
 20
     40–49
 30
 33
 27
 30
     50–59
 17
 24
 24
 18
     60–69
 10
 18
 13
 11
Household income



     ≤ $40,000*
 34
 50
 49
 37
Educational level*



     ≤ High school graduate
 39
 61
 58
 43

* Distribution differs significantly among categories. Tested by design-based Pearson chi-squared test P < .001).

Bierl et al. Population Health Metrics 2004 2:1   doi:10.1186/1478-7954-2-1