Table 4. Quality test of methodology of the included systematic reviews based on the critical appraisal sheets of the Centre of Evidence Based Medicine.
| First author/year of publication | Search strategy | Inclusion criteria selection | Quality of the studies | Results homogeneous | Presentation of results | Rating |
| Hickey et al. 201337 | + | + | + | + | + | 100% |
| Moja et al. 201214 | + | + | + | +/− | + | 90% |
| Zhou et al. 201111 | +/− | + | +/− | + | + | 80% |
| Liu et al. 200912 | +/− | + | + | +/− | − | 60% |
| Tsai et al. 20091 | +/− | + | +/− | + | + | 80% |
| Lee et al. 200815 | + | + | + | +/− | + | 90% |
| Levangie et al. 200813 | +/− | + | + | + | − | 70% |