Table 1.
Baseline characteristics of eligible studies.
| Study | Year | Country | Ethnicity | Type | Cases Number | Detection Method | Methylation site | Methylation site N(%) | Control style | NOS score |
|---|---|---|---|---|---|---|---|---|---|---|
| Zöchbauer13 | 2001 | USA | Caucasian | NSCLC | 107 | MSP | Promoter, CpG islands | 22(22.56) | A | 8 |
| Zhang3 | 2011 | China | Asian | NSCLC | 78 | MSP | Promoter, CpG islands | 4(5.13) | A | 7 |
| Guo15 | 2015 | China | Asian | NSCLC | 271 | MSP | Promoter, CpG islands | 81(29.89) | A | 7 |
| Feng18 | 2008 | USA | Caucasian | NSCLC | 49 | MSP | Promoter, CpG islands | 6(12.24) | A | 7 |
| Guo11 | 2004 | USA | Caucasian | NSCLC | 20 | MSP | Promoter, CpG islands | 14(70.00) | A | 8 |
| Esteller (1)19 | 1999 | USA | Caucasian | NSCLC | 22 | MSP | Promoter, CpG islands | 6(27.27) | A | 8 |
| Esteller (2)20 | 1999 | USA | Caucasian | NSCLC | 34 | MSP | Promoter, CpG islands | 10(29.41) | A | 8 |
| Ekim21 | 2011 | Turkey | Caucasian | NSCLC | 80 | MSP | Promoter, CpG islands | 51(63.75) | A | 7 |
| Brabender22 | 2003 | Germany | Caucasian | NSCLC | 90 | RT-MSP | Promoter, CpG islands | 34(37.78) | A | 8 |
| Lin23 | 2009 | China | Caucasian | NSCLC | 67 | MSP | Promoter, CpG islands | 1(1.49) | H | 7 |
| Yanagawa24 | 2007 | Japan | Asian | NSCLC | 101 | MSP | Promoter, CpG islands | 14(13.86) | A | 8 |
| Kontic25 | 2012 | Serbia | Caucasian | NSCLC | 65 | MSP | Promoter, CpG islands | 8(12.31) | A | 7 |
| Kim (1)26 | 2005 | Korea | Asian | AC | 72 | MSP | Promoter, CpG islands | 12(16.67) | A | 7 |
| Kim (2)27 | 2005 | Korea | Asian | NSCLC | 61 | MSP | Promoter, CpG islands | 38(62.30) | A | 8 |
| Ishiguro28 | 2013 | USA | Caucasian | NSCLC | 6 | MSP | Promoter, CpG islands | 2(33.33) | A | 8 |
| Vallböhmer29 | 2006 | Germany | Caucasian | NSCLC | 91 | RT-MSP | Promoter, CpG islands | 38(41.76) | A | 8 |
| Safar30 | 2005 | USA | Caucasian | NSCLC | 105 | MSP | Promoter, CpG islands | 11(10.48) | A | 7 |
| Drilon31 | 2014 | USA | Caucasian | NSCLC | 107 | MSP | Promoter, CpG islands | 9(8.41) | A | 7 |
| Pulling32 | 2003 | USA | Caucasian | AC | 237 | MSP | Promoter, CpG islands | 121(51.05) | A | 7 |
| Hayashi33 | 2002 | Japan | Asian | AC | 87 | MSP | Promoter, CpG islands | 31(35.63) | A | 8 |
| Liu34 | 2006 | USA | Caucasian | NSCLC | 121 | MSP | Promoter, CpG islands | 37(30.33) | A | 7 |
| Chan35 | 2002 | Hong Kong | Asian | NSCLC | 75 | MSP | Promoter, CpG islands | 11(14.67) | A | 6 |
| Furonaka36 | 2005 | Japan | Asian | NSCLC | 123 | MSP | Promoter, CpG islands | 47(38.21) | A | 7 |
| Wu37 | 2008 | Taiwan | Asian | NSCLC | 123 | MSP | Promoter, CpG islands | 111(50.45) | A | 7 |
| Harden38 | 2003 | USA | Caucasian | NSCLC | 90 | RT-MSP | Promoter, CpG islands | 14(15.56) | A | 8 |
| Buckingham39 | 2010 | USA | Caucasian | NSCLC | 132 | Pyrosequencing | Promoter, CpG islands | 14(10.61) | A | 7 |
| Topaloglu40 | 2004 | USA | Caucasian | NSCLC | 31 | RT-MSP | Promoter, CpG islands | 12(38.71) | A | 7 |
| Liu41 | 2010 | China | Asian | NSCLC | 98 | MSP | Promoter, CpG islands | 31(31.63) | H | 6 |
| Jin42 | 2010 | China | Asian | NSCLC | 94 | MSP | Promoter, CpG islands | 16(17.02) | A | 6 |
| Kang43 | 2011 | China | Asian | NSCLC | 77 | MSP | Promoter, CpG islands | 26(33.77) | H | 6 |
AC: adenocarcinoma; MSP: methylation-specific polymerase chain reaction; RT-MSP: Real-Time MSP; N: number of total; A: autologous control (the control sample from NSCLC themselves); H: heterogeneous control (the control sample from other individuals).