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| Study | English | French | German | Spanish | Italian | Other |
| Burdett 2003 | Grey 44 (98%); Published 75 (100%) | Grey 1 (2%) | ||||
| Fergusson 2000 | Overall 100 (88%) | Overall 6 (4%) | Overall 4 (3%) | Overall 2 (2%) | Overall 3 (2%) | Overall 1 Belgian (1%) |
| McAuley 2000 | Grey 99 (97%); Published 340 (93%) | Grey 2 (2%); Published 9 (2%) | Published 9 (2%) | Grey 1 (1%); Published 3 (1%) | Published 3 (1%) | Japanese: Published 1 |
