Table 1 Quality assessment of included case control studies
Author Year | Design | RoB_P | CrA_P | RoB_I | CrA_I | RoB_RS | CrA_RS | RoB_TaF |
|---|---|---|---|---|---|---|---|---|
Ang 2011 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Ang 2012 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Bergstrom 1991 | Case control | High | High | High | High | High | Low | High |
Branda 2013 | Case control | High | High | Unclear | Low | High | Low | High |
Cerar 2006 | Case control | High | High | Unclear | Low | Low | Low | High |
Cerar 2010 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Christova 2003 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Cinco 2006 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Dessau 2010 | Case control | High | High | Unclear | Low | High | Low | High |
Dessau 2013 | Case control | High | High | Unclear | Low | High | Low | High |
Flisiak 1996 | Case control | High | High | Unclear | Low | Low | Low | High |
Flisiak 1998 | Case control | High | High | Unclear | Low | Low | Low | High |
Goettner 2005 | Case control | High | High | Unclear | High | High | Low | High |
Goossens 2000 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Goossens 2001 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Gueglio 1996 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Hansen 1988 | Case control | High | High | High | High | Unclear | Low | High |
Hansen 1989 | Case control | High | High | High | High | Low | Low | High |
Hansen 1991 | Case control | High | High | High | Low | Low | Low | High |
Hernandez 2003 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Hofmann 1990 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Hofmann 1996 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Hofstad 1987 | Case control | High | High | High | High | Low | Low | High |
Hunfeld 2002 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Jovivic 2003 | Case control | High | High | High/Unclear* | High | Unclear | Low | High |
Kaiser 1998 | Case control | High | High | High | High | High | Low | High |
Kaiser 1999inf | Case control | High | High | High | High | High | Low | High |
Karlsson 1989eur | Case control | High | High | High/Unclear* | High | Low | Low | High |
Karlsson 1989siid | Case control | High | High | High | High | Low | Low | High |
Lahdenne 2003 | Case control | High | High | High | Low | Unclear | Low | High |
Lakos 2005 | Case control | High | High | Low | High/Low* | High | Low | High |
Lange 1991 | Case control | High | High | Unclear | High/Low* | Unclear | Low | High |
Lencakova 2008 | Case control | High | High | Low/Unclear* | High/Low* | Unclear | Low | High |
Marangoni 2005jmm | Case control | High | High | Unclear | Low | Low | Low | High |
Marangoni 2005new | Case control | High | High | Unclear | Low* | Low | Low | High |
Marangoni 2008 | Case control | High | High | Unclear | Unclear** | Unclear | Low | High |
Mathiesen 1996 | Case control | High | High | High/Low* | High/Low* | High | Low | High |
Mathiesen 1998 | Case control | High | High | High/Unclear* | High/Low* | Low | Low | High |
Nicolini 1992 | Case control | High | High | High | High | Unclear | Low | High |
Nohlmans 1994 | Case control | High | High | High/Unclear* | High/Low* | Unclear | Low | High |
Oksi 1995 | Case control | High | High | High/Unclear* | High/Low* | Unclear | Low | High |
Olsson 1991 | Case control | High | High | High | High | Unclear | Low | High |
Panelius 2001 | Case control | High | High | High | High | High | Low | High |
Putzker 1995 | Case control | High | High | Unclear | Low | High | Low | High |
Rauer 1995 | Case control | High | High | High | High | High | Low | High |
Reiber 2013 | Case control | High | High | High | Unclear | Low | Low | High |
Rijpkema 1994 | Case control | High | High | Unclear | High/Low* | Unclear | Low | High |
Ruzic 2002 | Case control | High | High | Unclear | Low | Unclear | Low | High |
Ryffel 1998 | Case control | High | High | Unclear | High | High | Low | High |
Schulte 2004 | Case control | High | High | Unclear | High | High | Low | High |
Smismans 2006 | Case control | High | High | Unclear | Low | High | Low | High |
Tjernberg 2007 | Case control | High | High | Unclear | Low/Unclear* | High | Low | High |
Tjernberg 2011 | Case control | High | High | Unclear | Low | High | Low | High |
VanBurgel 2011 | Case control | High | High | Unclear | Low | High | Low | High |
Wilske 1993 | Case control | High | High | High/Unclear* | High/Low* | High | Low | High |
Wilske 1999 | Case control | High | High | Unclear | High | High | Low | High |
Zoller 1990 | Case control | High | High | Unclear | High | Unclear | Low | High |