| Date | Event | Description |
|---|---|---|
| 15 February 2010 | Amended | Seven studies moved from 'awaiting assessment' to the excluded studies section, following assessment of full text/translation (Ahn 2006; Dubreuil 1986; Fisch 1983; Friedrich 1991; Giger 1979; Gutman 1995; Hoffmann 1994) |
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