Irritable bowel syndrome symptom severity improves equally with probiotic and placebo

Table 3 Irritable bowel syndrome symptom severity score item scores at baseline and end of intervention

Treatment		Baseline		Week 12	Change from baseline	Within-group comparison	Comparison with placebo	Comparison with low- and high-dose
	n	mean ± SD	n	mean ± SD	mean ± SD	P value	P value	P value
Severity of pain
Placebo	121	20.2 ± 20.6	118	18.5 ± 20.7	-2.2 ± 21.8	0.024	NA	0.303
Low-dose	124	24.1 ± 22.3	110	18.3 ± 18.6	-5.2 ± 24.4	0.005	0.640	NA
High-dose	122	24.3 ± 21.5	113	16.4 ± 17.8	-7.9 ± 21.8	< 0.001	0.189	NA
Number of days with pain over 10 d
Placebo	114	3.8 ± 2.8	111	2.8 ± 2.8	-1.0 ± 2.7	< 0.001	NA	0.234
Low-dose	115	4.4 ± 2.8	105	3.3 ± 2.6	-1.1 ± 2.9	< 0.001	0.470	NA
High-dose	121	4.1 ± 2.8	106	2.9 ± 2.4	-1.2 ± 2.5	< 0.001	0.634	NA
Bloating/Distension
Placebo	121	39.0 ± 28.0	118	30.7 ± 25.6	-8.3 ± 23.6	< 0.001	NA	0.669
Low-dose	122	40.5 ± 29.9	110	31.0 ± 25.7	-9.4 ± 29.6	< 0.001	0.905	NA
High-dose	122	37.1 ± 26.6	113	31.0 ± 27.3	-6.1 ± 25.8	0.002	0.535	NA
Satisfaction with bowel habits
Placebo	121	57.4 ± 22.6	118	47.3 ± 24.2	-10.3 ± 21.4	< 0.001	NA	0.964
Low-dose	124	59.4 ± 22.7	110	46.3 ± 19.8	-11.8 ± 22.4	< 0.001	0.701	NA
High-dose	122	55.0 ± 19.7	113	46.4 ± 22.6	-8.3 ± 23.3	< 0.001	0.757	NA
Interference of IBS with quality of life
Placebo	121	62.4 ± 17.0	118	48.6 ± 22.1	-13.9 ± 20.3	< 0.001	NA	0.210
Low-dose	124	60.8 ± 16.9	110	50.1 ± 19.4	-9.8 ± 16.5	< 0.001	0.133	NA
High-dose	122	59.8 ± 13.5	113	47.9 ± 16.5	-11.7 ± 13.6	< 0.001	0.509	NA

IBS: Irritable bowel syndrome.