TABLE 2.
Baseline characteristics of included studies.
| Author | Year | Country | Study design | Cases | Pathology a | Age (average ± SD) | Gender (M/F) | Follow up (year, average ± SD) | Multifocality (M/U b ) | Size (mm) |
|---|---|---|---|---|---|---|---|---|---|---|
| Kim JM 38 | 2006 | Korea | Retrospective cohort | 662 | PTC | 44.8 | 77/585 | 5.7 (0.25–9) | 266/396 | – |
| Grogan 34 | 2013 | America | Retrospective cohort | 269 | PTC | 35.9 ± 15.5 | 89/180 | 7.6 ± 8.1 (11–27) | 121/148 | – |
| Kim KJ 30 | 2015 | Korea | Retrospective cohort | 1661 | PTMC | 45.5 ± 11.5 (13–83) | 392/1917 | 5.6 ± 0.9 (0.1–7.3) | 549/1112 | – |
| Kim HJ 50 | 2015 | Korea | Retrospective cohort | 2095 | PTC | 46 ± 13 | 275/1820 | 7 (0.1–7.3) | 672/1423 | 16 ± 12 |
| Qu 42 | 2016 | China | Retrospective cohort | 496 | PTC | 43.8 ± 17.3 (7–85) | 160/336 | 10.4 ± 5.7 (0.8–28.6) | 209/287 | – |
| Tam 45 | 2016 | Turkey | Retrospective cohort | 912 | PTC | 49.2 ± 12.5 | 193/723 | 3.1 (0.5–8.3) | 308/604 | – |
| Wang W 46 | 2016 | China | Retrospective cohort | 2211 | PTC | 44.3 ± 11.8/44.4 ± 12.3 d | 507/1704 | 6 (0.5–15) | 636/1575 | – |
| Kim SK 39 | 2016 | Korea | Retrospective cohort | 5656 | PTC | 48.0 ± 10.4 | 1002/4654 | 5.1 (0.5–17.8) | 1529/4427 | 6 ± 2 |
| Wang F 21 | 2017 | Multinational c | Retrospective cohort | 2624 | PTC | 46 (35–58) | 385/2239 | 4.8 (2.2–8.9) | 1000/1624 | 15 (10–25) |
| Hwangbo 35 | 2017 | Korea | Retrospective cohort | 3282 | PTC | 47 ± 11 | 2897/385 | 5.8 (1.0–10.2) | 1285/1985 | 1.1 (0.1–2.0) |
| Kim Y 40 | 2017 | Korea | Retrospective cohort | 1928 | PTC | 53 (15–86) | 355/1573 | 7.8 (2–11.1) | 623/1305 | – |
| Khan 37 | 2018 | Pakistan | Retrospective cohort | 209 | PTC | 35.6 ± 13.8 (12–74) | 63/146 | 4.1 (1–16.3) | 87/122 | – |
| Xu 47 | 2018 | China | Retrospective cohort | 3607 | PTC | 47.5 ± 2 | 868/2739 | 5.7 (2.1–11.5) | 675/2932 | 6 ± 30 |
| Gui 17 | 2018 | China | Retrospective cohort | 541 | PTMC | 47.2 ± 12.3 | 128/413 | 3.5 (2–5) | 146/395 | 5.8 ± 2.4 |
| Li 33 | 2018 | China | Retrospective cohort | 570 | PTC | 45.3 ± 10.5/43.3 ± 11.5 d | 160/410 | 1.6 (1–2.2) | 285/285 | – |
| Ryu 44 | 2018 | Korea | Retrospective cohort | 390 | PTC | 46 (17–80) | 118/272 | 6.75 (0.5–13) | 142/248 | 1.61 ± 0.97 |
| Nam 41 | 2018 | Korea | Retrospective cohort | 2384 | PTC | 52 (12–86) | 495/1889 | 7.8 (2–10.9) | 142/248 | – |
| Geron 13 | 2019 | Israel | Retrospective cohort | 1039 | PTC | 48.4 ± 15.3 | 222/817 | 10.1 (4.7–16.3) | 534/505 | 15 (10–25) |
| Feng 33 | 2019 | China | Retrospective cohort | 442 | PTC | 45.4 ± 12.3 | 109/333 | 3.6 (0.9–8.25) | 119/323 | 12.3 ± 9.3 |
| Choi 31 | 2019 | Korea | Retrospective cohort | 2390 | PTC | 52 (12–88) | 516/1874 | 7.7 (2–11.9) | 892/1498 | 1.3 (0.8–1.8) |
| Shin 51 | 2020 | Korea | Retrospective cohort | 2902 | PTC | 51 (43–58) | 619/2283 | 7.4 (5.3–10.3) | 1580/1322 | 11 (7–14) |
| Jiang 36 | 2020 | China | Retrospective cohort | 4107 | PTC | 45.21 (12–82) | 909/3198 | 3.75 (2–11.9) | 1058/3826 | 9.2 (1–80) |
| Woo 48 | 2021 | Korea | Retrospective cohort | 1249 | PTC | 47.4 ± 11.4 | 154/1095 | 5.5 ± 2.7 | 487/762 | 10 ± 7 |
a
PTC, papillary thyroid carcinoma; PTMC, papillary thyroid microcarcinoma.
b
M/U, multifocal/unifocal.
c
America, China, Italy, Poland, Australia, Spain.
d
The data were presented separately.