Table 1.
General characteristics of included studies (n = 13).
| Characteristic | Categories | N (%) |
|---|---|---|
| Publication year | ≤2006 | 0 (0) |
| 2007–2010 | 3 (23.1) | |
| 2011–2015 | 4 (30.8) | |
| ≥2016 | 6 (46.2) | |
| Participants | Healthy adults | 6 (46.2) |
| Adults with health problems | 5 (38.5) | |
| Not reported | 2 (15.4) | |
| Country/Regions | China | 4 (30.8) |
| Korea | 4 (30.8) | |
| Japan | 4 (30.8) | |
| Taiwan | 1 (7.7) | |
| Study Design | Randomized control group | 3 (23.1) |
| Nonequivalent control group pre-posttest design | 5 (38.5) | |
| One group pre-post test design | 5 (38.5) | |
| Sample size | ≤20 | 7 (53.8) |
| 21–50 | 4 (30.8) | |
| ≥51 | 2 (15.4) | |
| Statement of ethical consideration | Yes | 12 (92.3) |
| No | 1 (7.7) |