Figure 1
Figure 2
Summary of the 13 meta-analyses or systematic reviews that qualified for this review_
| First author | Year | Country | Studies included | Outcome indicators |
|---|---|---|---|---|
| Corbitt et al14 | 2018 | Australia | 24 | ①② |
| Ortiz-Lucas M15 | 2013 | Spain | 10 | ①②③ |
| Didari T16 | 2015 | Iran, China | 15 | ①② |
| Zhang Y17 | 2016 | China | 21 | ①②③④ |
| Yuan F18 | 2017 | USA | 5 | ①② |
| Ford A C19 | 2014 | USA, UK, Canada | 43 | ①② |
| Tiequn B20 | 2015 | China | 6 | ①②④ |
| Li DQ21 | 2016 | China | 5 | ①②④⑤⑥ |
| Zhao ZF22 | 2014 | China | 19 | ①②③④⑤ |
| Shu XC23 | 2012 | China | 17 | ①②④ |
| Yao L24 | 2012 | China | 12 | ①②⑥ |
| Yue25 | 2015 | China | 17 | ①②③⑤ |
| Lan Y26 | 2011 | China | 32 | ①② |
Quality of meta-analyses and systematic reviews_
| AMSTAR question | Yes | Part | No |
|---|---|---|---|
| 1. Was an a priori design provided? | 12 | 1 | 0 |
| 2. Was a comprehensive literature search performed? | 5 | 5 | 3 |
| 3. Is it possible to replicate the search? | 8 | 5 | 0 |
| 4. Did the inclusion criteria permit gray literature? | 0 | 10 | 3 |
| 5. Was a list of studies (included and excluded) provided? | 0 | 0 | 13 |
| 6. Were the characteristics of the included studies provided? | 13 | 0 | 0 |
| 7. Was the scientific quality of the included studies assessed and documented? | 8 | 5 | 0 |
| 8. Were the methods used to combine the findings of studies appropriate? | 13 | 0 | 0 |
| 9. Was the effect size index chosen justified statistically? | 9 | 4 | 0 |
| 10. Was the likelihood of publication bias assessed? | 10 | 0 | 3 |
| 11. Was the conflict of interest included? | 6 | 0 | 7 |