Table 4.

Risk of Bias, Cohort Studies

	1	2	3	4	5	6	7	8	9	10	11
Moreno-García et al5	Yes	Yes	Cannot tell	Yes	Yes	Yes	Cannot tell	Yes	Yes	Yes	Yes
Richards et al3	Yes	Yes	Yes	Yes	Yes	Yes	Cannot tell	Yes	Yes	Yes	Yes
Basnet et al12	Yes	Yes	Yes	Yes	Cannot tell	Yes	Cannot tell	Cannot tell	Yes	Yes	Yes
Vanhomwegen et al1	Yes	Yes	Yes	Yes	Yes	Yes	Cannot tell	Yes	Yes	Yes	No
Ming et al7	Yes	Yes	Yes	Yes	No	Yes	Cannot tell	Yes	Yes	Yes	No
Heesom et al21	Yes	Yes	Yes	Cannot tell	No	Yes	Cannot tell	Yes	Yes	Yes	Yes
Waris et al14	Yes	Yes	Yes	Yes	Cannot tell	No	Cannot tell	Cannot tell	Yes	Yes	Yes
Hughes et al15	Yes	Yes	Yes	Cannot tell	Yes	Yes	Cannot tell	Cannot tell	Yes	Yes	Yes
Pink et al8	Yes	Yes	Yes	No	Yes	Yes	Cannot tell	Yes	Yes	Yes	Yes
Peters et al16	Yes	Yes	Yes	Cannot tell	Yes	Yes	Cannot tell	Yes	Yes	Cannot tell	Yes
May et al4	Yes	Yes	Yes	Cannot tell	Cannot tell	No	Cannot tell	Cannot tell	Cannot tell	Cannot tell	No
Heer et al17	Yes	Yes	Yes	Yes	Yes	Yes	Cannot tell	Yes	Yes	Yes	No
Tang et al19	Yes	Yes	Cannot tell	Yes	Yes	Yes	Cannot tell	Yes	Yes	Yes	Yes
Garrido et al20	Yes	Yes	Yes	Yes	Yes	Yes	Cannot tell	Yes	Yes	Yes	Yes
Roy et al18	Yes	Yes	Cannot tell	Yes	Yes	No	Cannot tell	Yes	Yes	Yes	Yes

Notes:

1. Did the study address a clearly focused issue?
2. Was the cohort recruited in an acceptable way?
3. Was the exposure accurately measured to minimize bias?
4. Was the outcome accurately measured to minimize bias?
5. Have the authors identified all important confounding factors?
6. Have they taken account of the confounding factors in the design and/or analysis?
7. Was the follow up of subjects complete enough?
8. Was the follow up of subjects long enough?
9. Do you believe the results?
10. Can the results be applied to the local population?
11. Do the results of this study fit with other available evidence?