Skip to main content

Table 1 Summary of NTM positive and negative sampling site variables

From: Factors associated with the isolation of Nontuberculous mycobacteria (NTM) from a large municipal water system in Brisbane, Australia

 

NTM Negative

NTM Positive

Significance (p value)

Sampling Site Factor (Mean ± SD)

   

Site elevation (meters above sea level)*

44.75 ± 40.12

43.78 ± 39.99

0.977

S

44.94 ± 41.92

44.88 ± 38.86

0.680

W

43.51 ± 26.54

43.26 ± 40.63

0.751

Pipe Diameter (cm)

438.01 ± 459.91

435.21 ± 461.92

0.954

S

403.23 ± 417.56

489.15 ± 513.25

0.211

W

553.94 ± 571.58

409.59 ± 434.81

0.103

Mains Age (years)

46.56 ± 19.53

48.94 ± 19.15

0.246

S

46.15 ± 19.83

50.97 ± 17.74

0.091

W

47.91 ± 18.71

47.97 ± 19.77

0.987

Pipe material

   

Asbestos cement

28 (30.8%

63 (69.2)

0.166

Cement lined†

77 (41.8)

107 (58.2)

PVC

6 (42.9)

8 (57.1)

Cast iron spun lined

30 (35.7)

54 (64.3)

Other‡

7 (63.3)

4 (36.4)

Sample type N (%)

   

Distribution

86 (37.1)

146 (62.9)

0.668

Reservoir

36 (39.1)

56 (60.9)

Trunk Main

26 (43.3)

34 (56.7)

Surface water source N (%)

   

Mt Crosby

120 (38.6)

191 (61.4)

0.995

Pine

14 (37.8)

23 (62.2)

Mixed

14 (38.9)

22 (61.1)

  1. *Elevation non normally distributed, square root transformation to analyse.
  2. †Cast iron, ductile iron or mild steel cement lined.
  3. ‡Steel unlined/ polyethylene/unknown.