Original text and correction
Original text:
There were some limitations in the study that should be mentioned. Firstly, seventeen studies out of the eighteen original studies used in our meta-analysis were case–control study design. This design is particularly vulnerable to potential biases (both selection and information biases). Secondly, some possible important residual confounders such as smoking and sex were not adjusted for in some studies. For example, one case–control study (7) only controlled for age. However, our subgroup analyses by whether residence, smoking or sex were controlled or not suggested that there is no significant difference in OR. Thirdly, limited original studies were adjusted for other food items in our study. Thus, the results of our study might be confounded by other food items. Additionally, OR with corresponding 95%CI for lung cancer associated with consumption of other food items were listed as a supplementary data. At last, the dose–response analysis between carrot intake and lung cancer risk was not performed because of limited data in original studies. Further studies with providing information of dose, cases and carrot consumption will be needed to assess the dose–response relationship.
Correction: Added the relevant hyperlink for the supplementary data.
Supplementary material
For supplementary material referred to in this article, please visit https://doi.org/10.1017/S0007114519001107
