1. Number Needed to Treat to Prevent a Single Case of Incontinence (NNT).
| Study | NNT Feces | NNT Flatus |
| (Sultan 1993a) | ‐710 | 50 |
| (MacLennan 2000) | 40 | 39 |
| (Chaliha 2001) | ‐50 | |
| (Chaliha 1999) | ‐131 | |
| (Eason 2002) | 160 | infinity |
| (Hannah 2004) | ‐1011 | 66 |
| (Hall 2003a) | ‐40 | 20 |
| (Lal 2003) | 34 | |
| (Fornell 2004) | 104 | ‐128 |
| (Pinta 2004a) | 12 | |
| (Abramov 2005) | 13 | ‐75 |
| (Goldberg 2003) | ‐171 | |
| (Groutz 1999a) | 35 | |
| (MacArthur 2005) | ‐741 | ‐456 |
| (Varma 2006) | 130 | |
| (Altman 2007) | 444 | 12 |
| (Bharucha 2006a) | 17 | |
| (Fritel 2007) | 38 | |
| (Guise 2008) | 11 | |
| (Melville 2005) | 64 | |
| (MacArthur 1997) | 140 |