Table 1. Characteristics of studies included in the meta-analysis.
| Author | Year | Country | Ethnicity | Na | Groupb | Diagnosis method | Treatmentc | Survival analysis | Analysis | NOS score |
|---|---|---|---|---|---|---|---|---|---|---|
| Fujiwara | 2013 | Japan | Asian | 274 | 4 | CT | NA | NA | NA | 9 |
| Fukui | 2016 | Japan | Asian | 1,368 | 4 | CT | Surgery | NA | NA | 9 |
| Gao | 2016 | China | Asian | 60 | 2 | HRCT | Mixed | OS | U | 9 |
| Hashimoto | 2016 | Japan | Asian | 685 | 4 | TSCT | Surgery | OS | M | 9 |
| Hata | 2016 | Japan | Asian | 250 | 4 | CT | Surgery | OS | M | 9 |
| Kumagai | 2014 | Japan | Asian | 365 | 4 | HRCT | Surgery | OS | M | 9 |
| Mimae | 2015 | Japan | Asian | 2,333 | 2 | CT | Surgery | OS | M | 9 |
| Minegishi | 2014 | Japan | Asian | 151 | 2 | CT | Mixed | OS | M | 9 |
| Otsuka | 2016 | Japan | Asian | 67 | 3 | HRCT | Surgery | OS | U | 9 |
| Sato | 2016 | Japan | Asian | 100 | 2 | CT | Surgery | OS | U | 9 |
| Takenaka | 2017 | Japan | Asian | 274 | 4 | CT | Surgery | OS | M | 8 |
| Usui | 2011 | Japan | Asian | 1,143 | 4 | HRCT | Mixed | OS | U | 8 |
| Zhang | 2016 | Japan | Asian | 985 | 2 | HRCT | Surgery | OS | M | 9 |
a, number of included patients; b, Group 4 includes CPFE group, fibrosis group, emphysema group, and normal group. Group 3 includes CPFE group, fibrosis group, and emphysema group. Group 2 includes CPFE group and non-CPFE group or includes CPFE group and fibrosis group; c, mixed includes patients undergoing surgery, chemotherapy, chemoradiotherapy, or other treatment. Surgery only includes patients getting surgery. NA, not available; OS, overall survival; M, multivariate analysis; U, univariate analysis; NOS, Newcastle-Ottawa Quality Assessment Scale; CT, chest computed tomography; HRCT, high resolution computed tomography; TSCT, thin-section computed tomography.