Bacterial community assemblages in classroom floor dust of 50 public schools in a large city: characterization using 16S rRNA sequences and associations with environmental factors

Table 1 Effect of environmental factors on dissimilarity in genus composition of paired classrooms using permutational multivariate analysis of variance (PERMANOVA) models

Environmental variable	Mean (SD)*	Full model (all categorical)**		Reduced model 1 (all categorical)**		Reduced model 2 (all categorical)**
Environmental variable	Mean (SD)*	R²	P value	R²	P value	R²	P value
Water damage score	0.17 (0.13)	0.01	< 0.001			0.01	< 0.001
Relative humidity	50.4 (9.9)	0.01	0.04	0.01	0.03	0.01	0.02
Temperature	81.1 (5.8)	0.01	< 0.001	0.01	< 0.001	0.02	< 0.001
Number of students	21.1 (9.3)	0.01	0.02	0.01	0.01	0.01	0.01
FCI score^†	38.8 (17.9)	0.02	< 0.001	0.02	< 0.001	0.02	< 0.001
Area		0.02	< 0.001	0.02	< 0.001
Floor material type		0.01	< 0.01	0.01	< 0.01	0.01	<0.01
Story in a building		0.01	< 0.001	0.01	< 0.001	0.01	< 0.001
Model residuals		0.89		0.90		0.91

*Mean and standard deviation (SD) for the numerical variables
**All environmental variables in these models were categorical. Area: north (n = 159), northeast (90), southeast (90), southwest (160); type of floor material: carpet (13), tile (208), wood (223), others (55); story in a building: 1st (165), 2nd (171), 3rd, or higher (143), ground or lower (20). Continuous variable was categorized into four levels based on quartile to create a categorical variable
†FCI facility condition assessment index

ISSN: 2049-2618