Table 4.

Individual IBS symptom scores—change from baseline of frequencies and intensities at 24 h and 28 days

Average of frequency and intensity	Placebo 24 h	PO 24 h	Placebo 28 days	PO 28 days
n	37	35	37	34
Abdominal bloating or distension
Change from baseline
Mean (SD)	−0.28 (0.560)	−0.59 (0.732)	−0.59 (0.780)	−1.10 (1.036)
Difference from placebo	NA	−0.30	NA	−0.51
P value*	NA	0.0586	NA	0.0474
Abdominal pain or discomfort
Change from baseline
Mean (SD)	−0.30 (0.478)	−0.74 (0.817)	−0.74 (0.983)	−1.50 (1.155)
Difference from placebo	NA	−0.45	NA	−0.76
P value*	NA	0.0138	NA	0.0183
Constipation (<3 stools/week)
Change from baseline
Mean (SD)	−0.23 (0.723)	−0.29 (0.700)	−0.38 (0.924)	−0.66 (1.283)
Difference from placebo	NA	−0.06	NA	−0.28
P value*	NA	0.8082	NA	0.3150
Diarrhea (>3 defecations/day)
Change from baseline
Mean (SD)	−0.38 (0.721)	−0.67 (0.970)	−1.14 (1.310)	−1.37 (1.275)
Difference from placebo	NA	−0.29	NA	−0.23
P value*	NA	0.1328	NA	0.3426
Pain at evacuation
Change from baseline
Mean (SD)	−0.27 (0.804)	−0.47 (0.757)	−0.53 (1.213)	−1.16 (0.959)
Difference from placebo	NA	−0.20	NA	−0.63
P value*	NA	0.4657	NA	0.0328
Passage of gas or mucus
Change from baseline
Mean (SD)	−0.22 (0.584)	−0.47 (0.822)	−0.70 (0.953)	−1.01 (1.190)
Difference from placebo	NA	−0.26	NA	−0.31
P value*	NA	0.1659	NA	0.3475
Sense of incomplete evacuation
Change from baseline
Mean (SD)	−0.28 (0.596)	−0.56 (0.829)	−0.68 (1.062)	−1.15 (1.077)
Difference from placebo	NA	−0.27	NA	−0.47
P value*	NA	0.1723	NA	0.1970
Urgency of bowel movement
Change from baseline
Mean (SD)	−0.22 (0.703)	−0.59 (0.919)	−0.84 (0.921)	−1.35 (1.048)
Difference from placebo	NA	−0.37	NA	−0.52
P value*	NA	0.0649	NA	0.0336

NA not applicable, PO peppermint oil, SD standard deviation

* P values derived from generalized linear models with the baseline score as a covariate