Table 4.

Home/familycharacteristics as univariate predictors of bacterial levels in household dust(d_p < 355μm). Significant associations (p < 0.05) are shown in boldand underlined.

		Dust concentration [cell eq./mg] Geometric mean (geometric standard deviation)			Dust loading [cell eq./m2] Geometric mean (geometric standard deviation)
Home characteristic	n#	S. maltophilia	Streptomyces	Mycobacterium	S. maltophilia	Streptomyces	Mycobacterium
Direct factors/sources
Number of inhabitants*
≤ 3	8	3147 (3.7)	2201 (3.6)	6.60 × 104 (3.9)	1.85 × 106 (5.1)	1.30 × 106 (8.1)	3.49 × 107 (8.8)
4	14	2073 (2.2)	2223 (2.2)	8.95 × 104 (2.1)	7.87 × 105 (3.5)	8.44 × 105 (4.2)	3.38 × 107 (3.7)
≥ 5	20‡	1920 (3.9)	1614 (3.5)	5.99 × 104 (3.5)	7.95 × 105 (3.9)	7.16 × 105 (4.5)	2.66 × 107 (4.0)
p		0.55	0.22	0.47	0.98	0.77	0.44
Presence of dogs†
No	24	2092 (3.4)	1308 (2.7)	4.53 × 104 (2.8)	9.83 × 105 (3.4)	6.14 × 105 (4.0)	2.03 × 107 (3.7)
Yes	18‡	2286 (3.1)	3144(2.9)	1.21 × 105 (2.7)	8.71 × 105 (4.8)	1.30 × 106 (5.9)	5.01 ×107 (4.8)
p		0.85	<0.01	<0.01	0.78	0.13	0.09
Indirect factors/sources
Reported water damage†
No	16	2120 (3.3)	1599 (3.4)	5.75 × 104 (3.6)	7.78 × 105 (3.6)	5.87 × 105 (4.6)	2.11 × 107 (4.3)
Yes	26‡	2203 (3.3)	2121 (2.8)	7.89 × 104 (2.7)	1.05 × 106 (4.3)	1.06 × 106 (5.0)	3.81 × 107 (4.4)
p		0.89	0.41	0.54	0.50	0.36	0.45
Reported visible mold†
No	19	2110 (3.1)	1371 (3.2)	4.81 × 104 (3.1)	8.46 × 105 (4.1)	5.49 × 105 (5.5)	1.93 × 107 (4.8)
Yes	23‡	2223 (3.4)	2499 (2.8)	9.62 × 104 (2.8)	1.02 × 106 (4.0)	1.21 × 106 (4.1)	4.46 × 107 (3.7)
p		0.93	0.05	0.04	0.69	0.08	0.10
Relative humidity(%)*
21.0-30.4	14	1286 (4.0)	1399 (3.4)	5.93 × 104 (4.0)	6.38 × 105 (4.2)	6.94 × 105 (3.6)	2.74 × 107 (3.9)
30.5-40.9	14‡	2355 (2.6)	2237 (3.2)	7.40 × 104 (3.0)	1.00 × 106 (2.9)	1.05 × 106 (4.5)	3.47 × 107 (3.8)
41.0-57.3	14	3397 (2.7)	2208 (2.6)	7.64 × 104 (2.6)	1.28 × 106 (4.9)	8.34 × 105 (7.3)	2.89 × 107 (5.9)
p		0.05	0.65	0.97	0.39	0.75	0.57
Temperature(°C)*
13.0-21.8	15	2127 (3.3)	2313 (2.9)	9.82 × 104 (2.6)	9.23 × 105 (5.7)	9.61 × 105 (5.3)	4.08 × 107 (4.5)
21.9-25.0	14	1982 (3.0)	2009 (2.8)	8.04 × 104 (3.6)	7.11 × 105 (2.9)	7.21 × 105 (4.3)	2.62 × 107 (4.7)
25.1-27.8	13‡	2397 (3.7)	1438 (3.5)	4.08 × 104 (2.8)	1.34 × 106 (3.4)	8.71 × 105 (5.6)	2.47 × 107 (4.3)
p		0.82	0.07	0.02	0.91	0.40	0.18
Surface moisture†
Air-dry	33‡	1793 (3.1)	1839 (3.1)	6.94 × 104 (3.1)	9.84 × 105 (4.1)	1.04 × 106 (4.7)	3.84 × 107 (4.1)
Borderline damp	6	6108 (2.9)	2095 (3.7)	8.77 × 104 (4.0)	1.04 × 106 (4.8)	3.57 × 105 (4.8)	1.49 × 107 (5.4)
p		0.02	0.75	0.64	0.93	0.14	0.16
General home characteristics
Flooring type†
Hard surface	7	5822 (1.7)	2316 (3.0)	9.70 × 104 (3.7)	6.47 × 105 (3.2)	2.57 × 105 (4.6)	1.08 × 107 (5.5)
Carpet/rug	35‡	1771 (3.2)	1832 (3.1)	6.52 × 104 (3.0)	1.01 × 106 (4.2)	1.07 × 106 (4.5)	3.74 × 107 (3.9)
p		0.01	0.57	0.39	0.45	0.03	0.05
Age of home (yr)*
> 77	13	4040 (3.0)	2833 (2.5)	1.17 × 105 (2.9)	1.94 × 106 (3.8)	1.36 × 106 (5.6)	5.20 × 107 (5.9)
35 -77	14	2563 (2.8)	1826 (2.8)	7.45 × 104 (2.8)	9.25 × 105 (4.2)	6.59 × 105 (5.0)	2.69 × 107 (4.7)
< 35	13‡	1146 (2.9)	1559 (3.3)	5.43 × 104 (2.6)	4.55 × 105 (3.2)	6.90 × 105 (4.5)	2.41 × 107 (3.1)
p		0.03	0.12	0.03	0.06	0.32	0.31

^*Linearly modeled variable. For this table,categorized into approximate tertiles.

^†Categorical variable.

^#Information on some home characteristics was missing and therefore, n does not add up to 42.

^‡One S. maltophilia dust concentration was excluded as an outlier, leaving n -1 samples for both S. maltophilia columns.

Note: Covariates thatwere significant at the 20% level in theseunivariate regression modelswere included in the initial multivariate model.