Table 4

Multivariable conditional logistic regression models of cryptosporidiosis among patients with AIDS according to pattern of tap water consumption and adjusted for potential confounders

Cases (n = 49)

Controls (n = 99)

Models and variables

N

(%)

N

(%)

Odds Ratio

95% CI

Model 1

Tap water at home

Never

2

(4)

31

(31)

1.00

Reference

Sometimes

20

(41)

30

(30)

7.70

1.63, 36.3

Always

27

(55)

38

(38)

6.76

1.37, 33.5

Tap water outside home

Never

29

(59)

81

(82)

1.00

Reference

Sometimes

4

(8)

8

(8)

1.59

0.38, 6.73

Always

16

(33)

10

(10)

3.16

1.23, 8.13

Exposure to fecal material^a

No

42

(86)

87

(88)

1.00

Reference

Yes

7

(14)

12

(12)

1.03

0.32, 3.36

Filtered municipal water

Filtered

27

(55)

51

(52)

1.00

Reference

Mixed

14

(29)

37

(37)

0.77

0.35, 1.74

Unfiltered

11

(16)

8

(11)

1.19

0.34, 4.20

Model 2: Composite water variable

Tap water exposure^b

Lowest exposure

2

(4)

29

(29)

1.00

Reference

Intermediate exposure

35

(71)

64

(65)

6.92

1.55, 30.9

Highest exposure

12

(24)

6

(6)

23.6

4.08, 137

Exposure to fecal material^a

No

42

(86)

87

(88)

1.00

Reference

Yes

7

(14)

12

(12)

0.96

0.30, 3.06

Filtered municipal water

Filtered

27

(55)

51

(52)

1.00

Reference

Mixed

14

(29)

37

(37)

0.81

0.37, 1.77

Unfiltered

11

(16)

8

(11)

1.23

0.38, 4.02

^aHad sex with partner who had diarrhea, cared for person with diarrhea, or touched something soiled with feces from person with diarrhea ^bModel 2 tap water composite exposure variable (Lowest = never consumed tap water both inside and outside the home; Highest = always consumed tap water both inside and outside the home)

Aragón et al. BMC Public Health 2003 3:2   doi:10.1186/1471-2458-3-2