Table 2.
Source of funding for the included studies (n = 23).
| Study, Year | Source of Funding | Type of Study |
|---|---|---|
| Alfadhil 2015 [31] | Supported by grant from King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia. | Prospective descriptive study |
| Antoniou 2020 [38] | This study was sponsored by an unrestricted educational grant from NovoNordisk. | Prospective study |
| Barquel 2016 [17] | None | Observational study |
| Braga 2019 [35] | Supported by “Fundação do Amparo à Pesquisa do Estado do Rio de Janeiro” (Faperj) | Prospective, longitudinal and observational study |
| Buhary 2016 [32] | None | Retrospective study |
| Capula 2013 [30] | Not mentioned | Observational study |
| Dalfra 2011 [28] | Not mentioned | Observational study |
| Gonzalez-quintero 2007 [33] | Not mentioned | Retrospective cohort study |
| Hu 2020 [24] | Supported by the National Natural Science Foundation of China under by Foundation for Innovative Research Groups of the National Natural Science Foundation of China; the National Key Research and Development Program of China; the Project of National Key Clinical Division of China, the Medical Scientific Research Foundation of Jiangsu Province of China; the Key Research and Development Program of Jiangsu Province of China; the Key Provincial Talents Program of Jiangsu Province of China; the Six talent peaks project of Jiangsu Province of China | Retrospective cohort study |
| Kansu-Celik 2019 [36] | Not mentioned | Retrospective cohort |
| Katon 2012 [21] | Funded by the University of Washington Department of Epidemiology. | Observational study |
| Krstevska 2009 [39] | Nothing mentioned | Observational study |
| Liu 2020 [25] | This study was funded by Sun Yat-Sen University Clinical Research 5010 Program and National Natural Science Foundation of China | Cohort study |
| Mane 2017 [34] | Received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. | Prospective cohort study |
| Mikkelsen 2011 [23] | Not mentioned | Cohort study |
| Olmos 2012 [18] | Not mentioned | Observational study |
| Pintaudi 2017 [29] | Not mentioned | Observational, retrospective, multicentre study |
| Sweeting 2017 [19] | Not mentioned | Retrospective cohort |
| Veres 2015 [37] | Not mentioned | Prospective cohort |
| Wong 2017 [20] | None | Retrospective review |
| Xin 2018 [22] | None | Retrospective study |
| Xu 2019 [26] | Supported by grants from the National Natural Science Foundation of China Grant Award, National Key Research and Development Program of China, the Project of National Key Clinical Division of China, and the Medical Scientific Research Foundation of Jiangsu Province of China. | Retrospective Cchort study |
| Zhao 2019 [27] | Not mentioned | Observational study |