Table 1.
Baseline characteristics of the 50 trials used in the meta-analysis
| Studies | Year | Patients source | Number of patients | Method | Stage | Study quality points |
|---|---|---|---|---|---|---|
| Cakir et al8 | 2011 | Turkey | 166 | IHC | I–IV | 6 out of 9 |
| Anagnostou et al3 | 2010 | USA/Greece | 534 | IHC | I–IV | 6 out of 9 |
| Grimminger et al9 | 2010 | Germany | 91 | RT-PCR | I–IIIA | 6 out of 9 |
| Jeong et al10 | 2010 | Republic of Korea | 39 | IHC | IIIA–IIIB | 5 out of 9 |
| Porebska et al11 | 2009 | Poland | 30 | IHC | I–IV | 6 out of 9 |
| Lee et al12 | 2009 | Republic of Korea | 50 | IHC | IIIB–IV | 7 out of 9 |
| Renouf et al13 | 2009 | Canada | 451 | IHC | I–II | 7 out of 9 |
| Zhao et al14 | 2008 | People’s Republic of China | 62 | IHC | I–IIIA | 6 out of 9 |
| Yoo et al15 | 2007 | Republic of Korea | 219 | IHC | I–III | 6 out of 9 |
| Hu et al16 | 2006 | People’s Republic of China | 88 | IHC | I–III | 6 out of 9 |
| Wang et al17 | 2006 | People’s Republic of China | 111 | IHC | I–III | 6 out of 9 |
| Yaren et al18 | 2006 | Turkey | 69 | IHC | I–IV | 6 out of 9 |
| Yilmaz et al19 | 2005 | Turkey | 46 | IHC | I–IV | 6 out of 9 |
| Groeger et al20 | 2004 | USA | 76 | IHC | I–IV | 5 out of 9 |
| Shibata et al21 | 2004 | Japan | 120 | IHC | I–III | 7 out of 9 |
| Kren et al22 | 2004 | USA | 102 | IHC | I–IIIA | 6 out of 9 |
| Ludovini et al23 | 2004 | Italy | 85 | IHC | IIIA–IV | 7 out of 9 |
| Grossi et al24 | 2003 | Italy | 213 | IHC | I–IIIA | 5 out of 9 |
| Huang et al25 | 2003 | USA | 91 | WB | I–IV | 6 out of 9 |
| Gregorc et al26 | 2003 | Italy | 102 | IHC | IIIA–IV | 7 out of 9 |
| Han et al27 | 2003 | Republic of Korea | 34 | IHC | IIIB–IV | 6 out of 9 |
| Krug et al28 | 2003 | USA | 31 | IHC | IIIB–IV | 8 out of 9 |
| Poleri et al29 | 2003 | Argentina | 53 | IHC | I | 8 out of 9 |
| Tomita et al30 | 2003 | Japan | 60 | IHC | IIIA–IV | 7 out of 9 |
| Lai et al31 | 2002 | Taiwan | 114 | IHC | I–IIIA | 6 out of 9 |
| Hanaoka et al32 | 2002 | Japan | 70 | IHC | I–III | 6 out of 9 |
| Han et al33 | 2002 | USA | 85 | IHC | I | 7 out of 9 |
| Hwang et al34 | 2001 | Republic of Korea | 53 | IHC | I–IIIB | 6 out of 9 |
| Laudanski et al35 | 2001 | Poland | 102 | IHC | I–IIIA | 6 out of 9 |
| Tanaka et al36 | 2001 | Japan | 162 | IHC | I | 8 out of 9 |
| Cox et al37 | 2000 | USA | 178 | IHC | I–IIIA | 6 out of 9 |
| Moldvay et al38 | 2000 | France | 226 | IHC | I–IV | 7 out of 9 |
| van de Vaart et al39 | 2000 | the Netherlands | 24 | IHC | IIIA–IIIB | 6 out of 9 |
| Chen et al40 | 1999 | Japan | 40 | IHC | I | 7 out of 9 |
| D’Amico et al41 | 1999 | USA | 408 | IHC | I | 8 out of 9 |
| Huang et al42 | 1999 | Japan | 203 | IHC | I–IIIB | 8 out of 9 |
| Mehdi et al43 | 1999 | USA | 241 | IHC | I–II | 6 out of 9 |
| Silvestrini et al44 | 1998 | Italy | 101 | IHC | I–III | 7 out of 9 |
| Anton et al45 | 1997 | USA | 427 | IHC | I–IV | 8 out of 9 |
| Apolinario et al46 | 1997 | the Netherlands | 116 | IHC | I–IIIA | 6 out of 9 |
| Higashiyama et al47 | 1997 | Japan | 174 | IHC | I–IIIB | 6 out of 9 |
| Ishida et al48 | 1997 | Japan | 114 | IHC | I–IIIA | 6 out of 9 |
| Koukourakis et al49 | 1997 | USA | 107 | IHC | I–IIIA | 6 out of 9 |
| Pastorino et al50 | 1997 | UK | 485 | IHC | I | 7 out of 9 |
| O’Neill et al51 | 1996 | Ireland | 54 | IHC | I–IV | 5 out of 9 |
| Ohsaki et al52 | 1996 | Japan | 99 | IHC | I–IV | 6 out of 9 |
| Fontanini et al53 | 1995 | Italy | 89 | IHC | I–IIIA | 5 out of 9 |
| Ritter et al54 | 1995 | USA | 126 | IHC | I | 7 out of 9 |
| Walker et al55 | 1995 | UK | 27 | IHC | I–IV | 6 out of 9 |
| Pezzella et al56 | 1993 | UK | 115 | IHC | I–III | 7 out of 9 |
Abbreviations: IHC, immunohistochemistry; RT-PCR, reverse transcription polymerase chain reaction; WB, Western blot.