Table 1. General characteristics of included studies.
| Sample size (n) | Histology | Control type | |||||||||
| Author | Year publication | Location | Age(y) | Gender(M/F) | T | C | Method | Sq | Ad | Ots | |
| Seike [13] | 2000 | Japan | 63.7(40–80) | 15/6 | 21 | 21 | MSP | 9 | 12 | 0 | NLT |
| Su [16] | 2000 | China | 58.9 | Na | 72 | 10 | MSP | 39 | 31 | 2 | NLT |
| He [31] | 2001 | China | Na | Na | 30 | 30 | MSP | 17 | 11 | 2 | NLT |
| Zochbauer [6] | 2001 | USA | Na | 76/31 | 107 | 104 | MSP | 43 | 45 | 19 | NLT |
| Bearzatto [30] | 2002 | Italy | 64 | 28/7 | 35 | 35 | RT-MSP | 10 | 18 | 7 | Plasm |
| Chen [25] | 2002 | Taiwan | Na | Na | 67 | 21 | MSP | Na | Na | Na | Sputum |
| He [32] | 2002 | China | Na | Na | 21 | 21 | MSP | 12 | 9 | 0 | BALF |
| Ng [17] | 2002 | Hong Kong | 60.2 | 25/8 | 33 | 33 | MSP | 13 | 15 | 5 | Plasm,BALF |
| Cai [33] | 2003 | China | 59.5 | 46/23 | 69 | 69 | MSP | 25 | 36 | 8 | Plasm |
| Harden [26] | 2003 | USA | 67(40–87) | 50/40 | 90 | 90 | q-MSP | 33 | 36 | 21 | NLT |
| Liu [18] | 2003 | China | Na | Na | 98 | 110 | MSP | 58 | 40 | 0 | Plasm sputum |
| Guo [27] | 2004 | USA | 66.1(42–83) | Na | 20 | 20 | MSP | 1 | 18 | 1 | NLT BLAF |
| Liu [14] | 2004 | China | Na | Na | 40 | 40 | MSP | 23 | 17 | 0 | Plasm |
| Zhang [34] | 2004 | China | Na | Na | 40 | 40 | MSP | 23 | 14 | 3 | NLT |
| Russo [19] | 2005 | USA | Na | Na | 48 | 48 | MSP | Na | Na | Na | Plasm |
| Georgiou [23] | 2007 | Greece | 63(38–76) | 32/3 | 35 | 35 | MSP | 15 | 17 | 3 | NLT BALF |
| Li [35] | 2006 | China | Na | 38/11 | 49 | 49 | MSP | 22 | 24 | 3 | Plasm |
| Rosalia [29] | 2006 | Italy | 60.2(51–74) | 20/9 | 29 | 18 | MSP | 5 | 23 | 1 | Sputum |
| Ulivi [15] | 2006 | Italy | Na | 49/12 | 61 | 61 | RT-MSP | 16 | 36 | 9 | Plasm |
| Wang [36] | 2006 | China | 32–73 | 42/5 | 47 | 47 | MSP | 31 | 7 | 9 | NLT |
| Belinsky [20] | 2007 | England | 62(37–80) | 49/23 | 72 | 72 | MSP | 22 | 29 | 21 | Plasm Sputum |
| Hong [22] | 2007 | Korea | Na | 63/18 | 81 | 81 | RT-MSP | 40 | 34 | 7 | NLT |
| Hsu(1) [21] | 2007 | Taiwan | 69 | 45/18 | 63 | 63 | q-MSP | 41 | 13 | 9 | NLT Plasm |
| Hsu(2) [24] | 2007 | Taiwan | Na | Na | 82 | 82 | MSP | 37 | 23 | 22 | NLTSputum |
| Kim [28] | 2007 | Korea | 63±8.4 | 80/19 | 99 | 99 | MSP | 61 | 38 | 0 | NLT |
| Yang [37] | 2007 | China | 56(31–77) | 34/15 | 49 | 49 | MSP | 26 | 23 | 0 | NLT |
| Zhang [38] | 2007 | China | Na | Na | 29 | 29 | MSP | 7 | 16 | 6 | NLT |
| Guo [39] | 2008 | China | 59±13 | 72/34 | 106 | 106 | MSP | 41 | 27 | 39 | Plasm |
| Wang [8] | 2008 | China | Na | 17/11 | 28 | 18 | MSP | 7 | 15 | 6 | NLT |
| Chen [40] | 2010 | China | 59.7(32–79) | 102/18 | 120 | 120 | MSP | 66 | 26 | 28 | NLT Plasm |
| Guo [41] | 2010 | China | 59.2 | 23/5 | 28 | 28 | MSP | Na | Na | Na | NLT |
| Zhang [42] | 2006 | China | 52.3(37–73) | 33/15 | 48 | 48 | MSP | 25 | 20 | 3 | NLT |
| Zhang [7] | 2011 | China | 61(32–79) | 162/38 | 200 | 200 | MSP | 104 | 59 | 37 | NLT |
| Sun [43] | 2012 | China | 65 | 96/24 | 120 | 120 | MSP | 32 | 72 | 16 | Sputum |
M = male; F = female; T = tumor; C = control; Sq = squamous cell carcinoma; Ad = adenocarcinoma; Ots = others; BALF = bronchoalveolar lavage; NLT:non-tumor lung issue; Na = not available.