Studies | Selection(stars) | Comparability(stars) | Outcome(stars) |
---|
Bepler et al. [6] | 4 | 2 | 3 |
Chang et al. [30] | 3 | 2 | 3 |
Chen et al. [21] | 4 | 2 | 3 |
Igawa et al. [31] | 3 | 2 | 3 |
Park et al. [22] | 3 | 2 | 3 |
Sun et al. [17] | 4 | 2 | 3 |
Takezawa et al. [18] | 3 | 2 | 3 |
Wang et al. [19] | 3 | 2 | 3 |
- The Newcastle–Ottawa Quality Assessment Scale is composed of three categories, selection, comparability and outcome. Stars are awarded to high-quality elements and are used to compare study quality in a quantitative manner. There are four items in the Selection category and three items in the Outcome category; a study can be awarded one star for each item in these categories. A maximum of two stars can be given for comparability.