Table 3.

Frequencies of operational taxonomic units in all samples and grouped by antibiotic use in the past 6 months

Classification	Mean frequency (SD)a			qvalueb
	All samples	Antibiotic use within past 6 mo
		Yes	No
Genus
Moraxella	22.04 (20.57)	21.18 (21.67)	22.65 (19.81)	0.68
Streptococcus	16.47 (17.61)	16.21 (16.82)	16.66 (18.21)	0.85
Corynebacterium	14.59 (15.25)	13.32 (15.61)	15.5 (14.97)	0.38
Dolosigranulum	11.9 (14.15)	7.47 (10.01)	15.06 (15.78)	0.02
Haemophilus	5.11 (10.54)	6.65 (12.57)	4.02 (8.70)	0.12
Staphylococcus	4.11 (8.25)	4.10 (7.98)	4.12 (8.46)	0.89
Lactococcus	2.25 (3.72)	2.91 (4.40)	1.78 (3.07)	0.12
Anoxybacillus	2.07 (3.69)	2.68 (4.31)	1.63 (3.11)	0.12
Enhydrobacter	0.80 (2.35)	0.82 (2.27)	0.79 (2.42)	0.85
Rothia	0.70 (1.64)	1.07 (2.33)	0.44 (0.78)	0.02
Neisseria	0.67 (1.59)	0.94 (1.90)	0.48 (1.30)	0.12
Gemella	0.44 (0.82)	0.55 (1.01)	0.36 (0.64)	0.15
Actinomyces	0.44 (0.94)	0.65 (1.27)	0.28 (0.57)	0.03
Veillonella	0.41 (0.81)	0.56 (1.05)	0.30 (0.56)	0.08
Granulicatella	0.40 (0.70)	0.52 (0.89)	0.32 (0.52)	0.12
Propionibacterium	0.34 (0.67)	0.33 (0.40)	0.35 (0.81)	0.85
Streptophyta	0.34 (1.93)	0.58 (2.92)	0.16 (0.52)	0.25
Family
Pasteurellaceae	2.8 (8.39)	4.08 (11.01)	1.88 (5.73)	0.12
Moraxellaceae	1.68 (4.80)	1.79 (5.14)	1.60 (4.56)	0.85
Enterobacteriaceae	0.82 (1.39)	1.01 (1.73)	0.68 (1.06)	0.15
Order
Actinomycetales	0.37 (0.27)	0.40 (0.27)	0.36 (0.27)	0.32
Corynebacterineae	0.31 (0.29)	0.27 (0.26)	0.33 (0.30)	0.12
Class
Gammaproteobacteria	0.98 (2.22)	0.84 (1.66)	1.08 (2.54)	0.50
Betaproteobacteria	0.78 (2.95)	0.40 (1.81)	1.04 (3.53)	0.12
Phylum
Proteobacteria	0.51 (0.85)	0.42 (0.63)	0.57 (0.97)	0.19
Bacteroidetes	0.46 (0.72)	0.46 (0.49)	0.47 (0.85)	0.85
Rare taxa combined	8.21 (8.00)	9.80 (9.08)	7.09 (6.94)	0.06

^aFor all samples, n = 240. By antibiotic use within past 6 months: yes, n = 100; no, n = 140.

^bqvalue from Metastats test of difference in frequencies between antibiotic use groups. Boldface indicates a significant result.