Table 6

Statistical power to detect genotype differences with this study sample

No with genotype SLC6A4 (Wt)% with phenotypeNo with genotype SLC6A4 (het/hom)⩾80% power† to detect this proportion (%) with phenotype
137Any FGID: 73%259Any FGID: ⩾85% (or⩽61%)
73IBS-C: 49%137IBS-C: ⩾69% (or ⩽29%)
78IBS-D: 53%170IBS-D: ⩾72% (or ⩽32%)
No with genotype α2C Del 322–325 (Wt)% with phenotypeNo with genotype α2C Del 322–325 (het/hom)⩾80% power† to detect this proportion (%) with phenotype
348Any FGID: 68%39Any FGID: ⩾88% (or ⩽48%)
183IBS-C: 40%22IBS-C: ⩾71% (or ⩽9%)
224IBS-D: 51%20IBS-D: ⩾82% (or ⩽20%)
No with genotype α2A −1291 (C→G) (Wt)% with phenotypeNo with genotype α2A −1291 (C→G) (het/hom)⩾80% power† to detect this proportion (%) with phenotype
210Any FGID: 67%182Any FGID: ⩾80% (or ⩽54%)
109IBS-C: 37%99IBS-C: ⩾57% (or ⩽17%)
140IBS-D: 51%108IBS-D: ⩾69% (or ⩽33%)
No with genotype α2A −1291 (C→G) (Wt) and SLC6A4 (Wt)% with phenotypeNo with genotype α2A −1291 (C→G) (het/hom) and SLC6A4 (het/hom)⩾80% power† to detect this proportion (%) with phenotype
†Based on two sample test for proportions using a two sided alpha level of 0.05.
IBS-C, irritable bowel syndrome with predominant constipation; IBS-D, irritable bowel syndrome with predominant diarrhoea; FGID, functional gastrointestinal disorders.
68Any FGID: 71%115Any FGID: >88% (or <52%)
39IBS-C: 49%66IBS-C: >76% (or <22%)
39IBS-D: 49%69IBS-D: >76% (or <22%)