Comparison of diagnostic methods of bile acid diarrhoea (BAD)
| Diagnostic method | Favourable points | Limitations |
| 75SeHCAT | Well established Predicts response to treatment | Involves radiation Limited availability in certain countries for example, unavailable in USA |
| C4 | No radiation Simple | Diurnal variation Fasting sample Not widely available (in the UK as a research tool) |
| FGF19 | No radiation Simple Commercial assay available | Diurnal variation Requires further validation |
| Faecal bile acids/faecal metabolomics | No radiation | Cumbersome 48 hours sample collection versus spot test Not widely available Poor patient compliance |
| Urine | Easy collection | Experimental Not widely available |
| Therapeutic trial | Easily available | Unreliable Poor response does not exclude diagnosis of BAD Not cost-effective Delays diagnosis and affects patients quality of life. |
FGF19, fibroblast growth factor 19 .