Table 1 Assessment of consideration of confounding bias in Abstracts and Discussion [26]

1. “Do the authors mention confounding using explicitly the terms “confounder(s),” “confounding,” “confound,” or do they allude to it without using those terms, or is confounding not considered at all?” [26]

2. “Do the authors mention bias using explicitly the term “bias”?” [26]

3. “Do the authors mention specific confounders that have not been adjusted for? (If yes, what were the reasons? If not, were there unspecified unmeasured confounders without specifically stating which ones?” [26]

4. “Do the authors state that their main findings are likely, possibly, or unlikely affected by residual confounding?” [26]

5. “Do the authors state that their findings need to be interpreted with caution due to confounding?” [26]

6. “Do the authors call for caution or indicate limitations or uncertainty due to possible confounding or other bias in their conclusions?” [26]