Table 2.

Mann–Whitney test results showing taxonomic contrasts between healthy controls and IBS-C and IBS-D patients, as well as before and after rifaximin treatment in all IBS patients.

IBS C-type patients / Healthy controls
Taxon	Mann-Whitney test statistic	p-Value	Mean abundance- C	Mean abundance - HC	q-Value
Bacteroides	25	0.000018	0.115	0.35	0.0022
Coriobacteriaceae	266	0.000310	0.00179	0.00033	0.0155
Ruminococcaceae	258	0.000370	0.057	0.027	0.0155
Clostridiales	253	0.00076	0.093	0.023	0.024
Rhodospirillaceae	248.5	0.00192	0.00032	0.000035	0.038
Clostridiales - Family_XIII_Incertae_Sedis	249	0.00209	0.0024	0.00059	0.038
Granulicatella	246	0.0028	0.000178	0.000108	0.040
Uncultured Ruminococcaceae	246	0.0028	0.0199	0.0064	0.040
Eubacterium	243	0.0031	0.000140	0.000021	0.040
Firmicutes	240	0.0039	0.030	0.0134	0.042
Acetanaerobacterium	240	0.0052	0.0028	0.00060	0.046
Catenibacterium	237	0.0055	0.0096	0.00035	0.046
Lachnospiraceae	235	0.0068	0.092	0.063	0.054
Clostridia	234	0.0076	0.0035	0.00144	0.056
Parabacteroides	65	0.0083	0.0108	0.025	0.058
IBS D-type patients / Healthy controls
Taxon	Mann-Whitney test statistic	p-Value	Mean abundance - D	Mean abundance - HC	q-Value
Porphyromonadaceae	244	0.00070	0.00158	0.0040	0.053
Alistipes	248	0.00087	0.026	0.049	0.053
IBS patients before and after treatment (paired test)
Taxon	Mann-Whitney test statistic	p-Value	Mean abundance – before treatment	Mean abundance – after treatment	q-Value
Bilophila	564	0.000201	0.0028	0.0043	0.025
Clostridiales	1935	0.00050	0.030	0.021	0.027
Catabacter	1328	0.00084	0.00030	0.000193	0.027
Parasutterella	621	0.0032	0.0059	0.0097	0.055
Clostridiales - Family_XIII_Incertae_Sedis	1745	0.0033	0.00070	0.00034	0.055
Clostridiales - Family_XIII_Incertae_Sedis uncultured	1790	0.0034	0.00048	0.00029	0.055
Firmicutes	1834	0.0036	0.0155	0.0106	0.055