| Study | Reason for exclusion |
|---|---|
| Aksoylar 2001 | 'Day' randomised rather than participant or episode. Results reported per participant |
| Alavi 1985 | < 18‐year‐olds not extractable |
| Basch 2011 | Not randomised |
| Bauduer 1999 | < 18‐year‐olds not extractable |
| Bonaventura 1999 | < 18‐year‐olds not extractable |
| Brice 1989 | < 18‐year‐olds not extractable |
| Corapcioglu 2005 | Randomisation not adhered to |
| Dana 1987 | < 18‐year‐olds not extractable |
| Delgado 1983 | < 18‐year‐olds not extractable |
| Fauser 1998 | < 18‐year‐olds not extractable |
| Feng 2000 | < 18‐year‐olds not extractable |
| Feng 2002 | < 18‐year‐olds not extractable |
| Forni 2000 | < 18‐year‐olds not extractable |
| Friedman 2000 | < 18‐year‐olds not extractable |
| Gagen 1984 | < 18‐year‐olds not extractable |
| Gez 1989 | < 18‐year‐olds not extractable |
| Gorena 1996 | Not randomised |
| Hatae 1989 | Not randomised |
| Herrstedt 2007 | < 18‐year‐olds not extractable |
| Hirota 1993a | Multiple cross‐overs, uncertainly about how randomised the data are, no data to extract parallel or AB/BA results |
| Jara 1999 | < 18‐year‐olds not extractable |
| Joss 1994 | < 18‐year‐olds not extractable |
| Kearsley 1989 | < 18‐year‐olds not extractable |
| Keyhanian 2009 | Participants not < 18 |
| Koseoglu 1998 | Multiple cross‐overs, uncertainly about how randomised the data are, no data to extract parallel or AB/BA results |
| Luisi 2006 | Multiple cross‐overs, uncertainly about how randomised the data are, no data to extract parallel or AB/BA results |
| Matsuoka 2003 | < 18‐year‐olds not extractable (only 2 participants, 1 in each arm) |
| Nathan 2006 | n‐of‐1 randomisation |
| NCT00429702 2007 | Terminated without publication of results |
| Needles 1999 | < 18‐year‐olds not extractable |
| Onat 1995 | < 18‐year‐olds not extractable |
| Pillai 2011 | < 18‐year‐olds not extractable |
| Relling 1993 | Multiple courses per randomised participant but without any data to enable cluster or first course assessment |
| Roila 1995 | < 18‐year‐olds not extractable |
| Roila 1996 | < 18‐year‐olds not extractable |
| Roila 1998 | < 18‐year‐olds not extractable |
| Roila 2000 | < 18‐year‐olds not extractable |
| Stiakaki 1999 | Multiple courses per randomised participant but without any data to enable cluster or first course assessment |
| Sumer 1988 | Multiple courses per randomised participant but without any data to enable cluster or first course assessment |
| Tian 2011 | Participants not < 18 |
| Tsukuda 2009 | Participants not < 18 |
| Yalcin 1999 | < 18‐year‐olds not extractable |
| Yonemura 2009 | Participants not < 18 |
AB/BA = alternating cross‐over trial with each participant receiving either one treatment (A) followed by a second (B), or in the opposite sequence (B then A)