Table 1. Characteristics of studies included in the meta-analysis.
| First author & year | Country or region | No. of patients | Mean age | Gender(M/F) | (C+N)/T | Level of evidence | Stage | Clinicopathological features | Method | antibody source | Dilution | Blind evaluation | Definition standard* | ProvidedOS data | ||
| Jin 2014 | Korea | 302 | 54.88(25–77) | 254/48 | (233+10)/243 | 5 | I–IV | D, T | IHC | NR | NR | Yes | CS | Yes | ||
| Lee 2014 | USA | 89 | 51 (20–75) | 78/11 | (21+8)/29 | 4 | I–IV | D | IHC | (BD Biosciences, San Diego, CA) | 1∶50 | Yes | CS | NR | ||
| Witjes 2013 | Netherlands | 47 | 65 (21–82) | 23/24 | (0+16)/16 | 4 | NR | D,T | IHC | (DAKO, Japan) | NR | Yes | ≥Focal/diffuse | NR | ||
| Geng 2012 | China | 85 | NR | 77/8 | (52+6)/58 | 4 | I–IV | D,T | IHC | (BD Biosciences, USA) | 1∶400 | Yes | CS | Yes | ||
| Zhao 2012 | China | 97 | 52.86 | 82/15 | (?+?)/66 | 5 | I–IV | D,M | IHC | (Santa Cruz Biotech, USA) | 1∶100 | Yes | CS | Yes | ||
| Feng 2011 | China | 63 | 45.8±10.6 (24–74) | 51/12 | (35+0)/35 | 4 | NR | D,M | IHC | (BD Biosciences, San Diego, CA) | NR | Yes | >10%cells | NR | ||
| Cheng 2011 | Hong Kong | 25 | 47.92(14–72) | 23/2 | (8+0)/8 | 3 | NR | D | IHC | (DAKO, Japan) | 1∶100 | Yes | CS | NR | ||
| Liu 2010 | China | 200 | NR | 169/31 | (?+?)/87 | 4 | I–IIIa | D,T,M | IHC | (BD Biosciences, San Diego, CA) | NR | Yes | Stronger than non-cancerous | Yes | ||
| Zulehner 2010 | Austria | 133 | 54.7±9 | 113/20 | (0+78)/78 | 4 | NR | D,M, T | IHC | (Transduction Laboratories, Lexington, UK) | 1∶100 | Yes | > low staining | NR | ||
| Du 2009 | China | 43 | 49(29–72) | 36/7 | (17+0)/17 | 3 | NR | D,T,M | IHC | (Abgent Biotechnology, CA) | 1∶50 | Yes | > weak | NR | ||
| Yu 2009 | China | 314 | NR | 266/48 | (?+?)/126 | 5 | I–III | D,T,M | IHC | (Transduction Laboratories, Lexington, KY) | 1∶200 | Yes | >10% cells | Yes | ||
| Yang 2009 | Taiwan | 123 | NR | 104/19 | (?+?)/53 | 5 | I–IV | D,T,M | IHC | (Abcam plc.) | 1∶1000 | Yes | >10% cells | Yes | ||
| Korita 2008 | Japan | 125 | 63(16–79) | 88/37 | (0+16)/16 | 3 | NR | D,T | IHC | (Novocastra Laboratories Ltd, Newcastleupon-Tyne, United Kingdom) | 1∶200 | Yes | CS | NR | ||
| Zhai 2008 | China | 97 | 54(34–72) | 67/30 | (36+6)/42 | 3 | I–IV | D,T,M | IHC | (Santa Clauze Corporation, USA) | 1∶200 | Yes | CS | Yes | ||
| Park 2005 | Korea | 92 | 51.6(26–89) | 75/17 | (?+?)/30 | 3 | I–IV | D | IHC | (Transduction Laboratories, Lexington, Lexington, KY) | NR | Yes | CS | NR | ||
| Tien 2005 | Japan | 32 | 64(36–86) | 20/8 | (7+8)/15 | 3 | NR | D | IHC | (BD Biosciences, San Jose, CA) | 1∶200 | Yes | Stronger than non-cancerous | NR | ||
| Schmitt Graff 2003 | Germany | 196 | 65.3(10.7–86.0) | 157/39 | (84+73)/157 | 3 | I–IV | NR | IHC | (Transduction Laboratories, Lexington, KY, USA) | 1:6000 | Yes | ≥Focal | Yes | ||
| Inagawa 2002 | Japan | 51 | 63.5(45–79) | 33/18 | (0+18)/18 | 4 | NR | D | IHC | (Transduction Laboratories, Lexington, KY) | 1∶200 | Yes | Stronger than non-cancerous | NR | ||
| Suzuki 2002 | Japan | 50 | 62.4±9.9 | 38/12 | (42+11)/53 | 3 | NR | D,M,T | IHC | (Transduction Laboratories, Lexington, KY) | 1∶200 | Yes | Stronger than non-cancerous | NR | ||
| Endo 2000 | Japan | 107 | 60(17–80) | 87/20 | (?+?)/84 | 4 | NR | D | IHC | (Transduction Laboratories, Lexington, KY) | 1∶100 | Yes | CS | Yes | ||
| Huang 1999 | Japan/Switzerland | 22 | 62.7±6.3(49–75) | 17/5 | (0+11)/11 | 3 | NR | D | IHC | (Transduction Laboratories, Lexington, KY) | 1∶1000– 2000 | Yes | ≥ Focal | NR | ||
| Ihara 1996 | Japan | 41 | 60.1(42–77) | 38/3 | (?+?)/58 | 3 | NR | D | IHC | (Transduction Laboratories, Lexington, KY) | 10 mg/ml | Yes | CS | NR | ||
CS: complex score combining intensity and percentage; IHC: immunohistochemistry; D: histologic differentiation degree; T: depth of tumor invasion; M: metastasis; OS: overall survival; NR: not reported; *: The definition standard of β-catenin overexpression in cytoplasm or nucleus; (C+N)/T: the number of tissue samples with β-catenin overexpression in cytoplasm(C) (+) nucleus (N); C: cytoplasm; N: nucleus; T: total, T = C+N; ?: no information was provided.