Table 7 Quality appraisal for observational studies
Author year | 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. Believe results | 12. Results be applied | 13. Results fit evidence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Carlsson 2014 [43] | u | y | y | y | y | y | u | y | y | y | y | y | y |
Collier 2011 [44] | y | y | y | y | y | y | u | y | u | n | n | y | u |
Gelber 2013 [45] | y | n | u | u | y | y | u | y | n | y | n | n | na |
Testa 2014 [46] | y | y | y | y | y | y | u | y | y | y | u | y | u |