Table 2.
Subject characteristics
| Ref. | Age (yr) | Female gender | BMI (kg/m2) | Condition |
| Agrawal et al[14] | 40 | 100% | 25 | IBS-C |
| Bartram et al[15] | 23 | 58% | - | None |
| Bouvier et al[16] | 33 | 50% | 22 | None |
| Holma et al[17] | 44 | 92%1 | 24 | Constipation |
| Hongisto et al[18] | 43 | 100% | 24 | Constipation |
| Malpeli et al[19] | 41 | 100% | - | Constipation |
| Marteau et al[20] | 27 | 100% | 21 | None |
| Rosenfeldt et al[21] | 25 | 0% | - | None |
| Rosenfeldt et al[21] | 25 | 0% | - | None |
| Sairanen et al[22] | 39 | 64% | 25 | None |
| Waller et al[23] | 44 | 65% | 31 | Constipation |
| Waller et al[23] | 44 | 65% | 32 | Constipation |
| Krammer et al[24] | 50 | 100% | - | Constipation |
1
Percentage estimated from larger study cohort. BMI: Body mass index; IBS-C: Irritable bowel syndrome, constipation predominant; “-“: Represents missing data.