Table 2.
Information of SSNs and results.
| Study | Size of baseline SSNs (mm) ± SD | Definition of growth | Assessment types of SSNs | Including quantitative initial CT features | Statistically significant results |
|---|---|---|---|---|---|
| Bak et al. (12) | 11.7 ± 5.4 | DE | VA | Diameter of GGO component; volume; mass; density; histogram | Histogram |
| Tamura et al. (13) | 11.4 ± 4.2 | DE | VA | Diameter; mean CT attenuation | Mean CT attenuation |
| Eguchi et al. (14) | 7.4 ± 2.8 | DE | VA | Diameter; mean CT attenuation | Diameter; mean CT attenuation |
| Chang et al. (15) | 5.5 | D | TDR | Diameter | Diameter |
| Borghesi et al. (16) | 16.5 | VDT; MDT | VA | Diameter; volume; mean CT attenuation; mass | None |
| Oda et al. (17) | 13.0 ± 4.9 | VDT | VA | Diameter; mean CT attenuation | Mean CT attenuation |
| Hiramatsu et al. (18) | 8.3 | DSE | VA | Diameter; mean CT attenuation | Diameter |
| Lee et al. (19) | 7.8 ± 4.4 | D | VA | Diameter | Diameter |
| Kobayashi et al. (20) | 9.0 | D | VA | Diameter | Diameter |
| Matsuguma et al. (21) | NM | DSE | VA | Diameter | Diameter |
D, an increase in diameter ≥2 mm; DE, an increase in diameter ≥2 mm or an emerging solid portion; DSE, an increase in diameter or the size of the solid part ≥2 mm or an emerging solid portion; SSN, subsolid nodule; GGO, ground glass opacity; MDT, mass doubling time; NM, not mentioned; TDR, tumor shadow disappearance rate; VA, visual assessment; VDT, volume doubling time.