Funding for this research was provided by:
Tehran University of Medical Sciences
Received: 15 April 2020
Accepted: 23 March 2021
First Online: 1 April 2021
: The main project on glioma was first ethically approved by the Iran National Nutrition and Food Technology Research Institute in 2009, before the study (Ethical code: 39414). Then, based on the main dataset, other projects were defined, each with a different exposure. Mostly, each of these projects that were later written based on that dataset, has its own approvals. For the current study, the Medical Ethics Committee of Tehran University of Medical Sciences ethically approved the study (2020/06/22, Ethical code: IR.TUMS.MEDICINE.REC.1399.162). All participants gave oral informed consent before entering the study.
: Not applicable.
: The authors declare that they have no competing interests.