Table 5 Quality appraisal for observational studies
Source | Type of study | 1. Focused issue | 2. Appropriate method | 3. Recruitment | 4. Selection of controls | 5. Exposure measured | 6. Outcome measured | 7. Identified confounding factors | 8. Confounding factors in design/analysis | 9. Follow up complete | 10. Follow up long | 11. Results | 12. Precise results | 13. Believe results | 14. Results be applied | 15. Results fit evidence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Chang et al. 2015 [33] | Cohort study | Y | Y | Y | NA | Y | Y | Y | Y | Y | Y | Â | Â | Y | Y | N |
Chen et al. 2015 [34] | Cohort study | Y | Y | Y | NA | Y | Y | Y | Y | Y | Y | Â | Â | Y | Y | N |
Driessen et al. 2014 [45] | Retrospective population based cohort study | Y | Y | Y | NA | Y | Y | Y | Y | Y | Y | Â | Â | Y | Y | N |
Giorda et al. 2015 [48] | Case-control study | Y | Y | Y | Y | Y | Y | Y | Y | Y | U | Â | Â | Y | Y | N |
Mistry et al. 2011 [57] | retrospective observational survey | Y | U | Y | NA | U | Y | U | U | NA | NA | Â | Â | Y | Y | Y |
Ou et al. 2015 [35] | Cohort study | Y | Y | Y | NA | Y | Y | Y | Y | Y | Y | Â | Â | Y | Y | N |
Penfornis et al. 2012 [49] | Prospective cohort study | Y | Y | Y | N | U | Y | U | U | Y | Y | Â | Â | Y | U | Y |
Shih et al. 2015 [36] | Nested case-control study | Y | Y | Y | Y | Y | Y | U | Y | NA | NA | Â | Â | U | U | N |
Sicras-Mainar and Navarro-Artieda 2014 [50] | Retrospective longitudinal study | Y | U | U | U | Y | U | U | N | U | U | Â | Â | U | U | U |
Tziomalos et al. 2015 [51] | Observational study | Y | Y | U | NA | Y | Y | U | U | NA | NA | Â | Â | U | U | N |
Viljoen et al. 2013 [46] | Observational study | Y | U | N | U | U | U | U | U | NA | NA | Â | Â | Y | Y | Y |
Yu et al. 2015 [47] | Cohort study with a nested case-control analysis | Y | N | Y | Y | Y | Y | N | Y | NA | NA | Â | Â | Y | Y | N |