Table 1.
Selected study characteristics of included articles (n = 20).
| Study Characteristic | No. (%) |
|---|---|
| Year published | |
| 2011–2014 | 5 (25) |
| 2015–2019 | 15 (75) |
| Country of origin | |
| USA | 6 (30) |
| Canada | 1 (5) |
| UK | 1 (5) |
| Denmark | 2 (10) |
| Spain | 2 (10) |
| China | 6 (30) |
| Taiwan | 1 (5) |
| Japan | 1 (5) |
| Design | |
| Randomized control trial | 1 (5) |
| Retrospective cohort | 13 (65) |
| Prospective cohort | 6 (30) |
| Comparative arm | |
| Yes | 6 (30) |
| No | 14 (70) |
| Sample source | |
| Single-center | 14 (70) |
| Multi-center | 4 (20) |
| Not stated | 2 (10) |
| Data source | |
| Institutional data | 12 (60) |
| National Cancer Database | 3 (15) |
| Cleveland Clinic colorectal cancer registry | 1 (5) |
| Colorectal Carcinoma Database | 1 (5) |
| Not stated | 3 (15) |