Table 2. Newcastle-Ottawa Risk of Bias Assessment.
| Author’s name | Study design | Selection | Comparability | Exposure | Score | Risk of bias |
| Hoarau, 2010 [10] | Cohort | 3 | 0 | 1 | 4 | Intermediate |
| Chaaithanya, 2011 [36] | Cohort | 3 | 0 | 2 | 5 | Intermediate |
| Kelvin, 2011 [18] | Cohort | 3 | 0 | 2 | 5 | Intermediate |
| Chow, 2011 [29] | Cohort | 2 | 0 | 2 | 4 | Intermediate |
| Chopra, 2012 [28] | Cohort | 3 | 0 | 2 | 5 | Intermediate |
| Lohachanakul, 2012 [20] | Cohort | 4 | 0 | 0 | 4 | Intermediate |
| Moro, 2012 [41] | Cohort | 4 | 1 | 3 | 8 | Low |
| Kam, 2012 [34] | Cohort | 2 | 0 | 0 | 2 | High |
| Gérardin, 2013 [40] | Cohort | 4 | 1 | 2 | 7 | Low |
| Venugopalan, 2014 [30] | Cohort | 3 | 0 | 1 | 4 | Intermediate |
| Chang, 2018 [39] | Cohort | 4 | 1 | 2 | 7 | Low |
| Nayak, 2020 [42] | Cohort | 4 | 0 | 2 | 6 | Intermediate |
| Jacob-Nascimento, 2021 [63] | Cohort | 4 | 2 | 1 | 7 | Low |
| Alves de Souza, 2022 [15] | Cohort | 3 | 0 | 1 | 4 | Intermediate |
| Chirathaworn, 2010 [64] | Case-Control | 2 | 0 | 3 | 5 | Intermediate |
| Wauquier, 2011 [24] | Case-Control | 3 | 0 | 3 | 6 | Intermediate |
| Chirathaworn, 2013 [16] | Case-Control | 1 | 0 | 3 | 4 | Intermediate |
| Schilte, 2013 [38] | Case-Control | 4 | 1 | 3 | 8 | Low |
| Kashyap, 2014 [17] | Case-Control | 1 | 0 | 3 | 4 | Intermediate |
| Reddy, 2014 [65] | Case-Control | 1 | 1 | 3 | 5 | Intermediate |
| Rojas, 2015 [43] | Case-Control | 4 | 1 | 3 | 8 | Low |
| Dutta, 2017 [66] | Case-Control | 3 | 2 | 3 | 8 | Low |
| Chattopadhya, 2017 [27] | Case-Control | 2 | 1 | 3 | 6 | Intermediate |
| Banerjee, 2018 [67] | Case-Control | 2 | 1 | 3 | 6 | Intermediate |
| Tanabe, 2019 [68] | Case-Control | 1 | 0 | 3 | 4 | Intermediate |
| Cavalcanti, 2019 [31] | Case-Control | 3 | 1 | 2 | 6 | Intermediate |
| Ninla-Aesong, 2019 [35] | Case-Control | 4 | 1 | 3 | 8 | Low |
| Sánchez-Arcila, 2020 [23] | Case-Control | 2 | 0 | 3 | 5 | Intermediate |
| Cavalcanti, 2020 [32] | Case-Control | 2 | 1 | 2 | 5 | Intermediate |
| Krishnan, 2021 [19] | Case-Control | 1 | 1 | 2 | 4 | Intermediate |
| Rocha, 2022 [33] | Case-Control | 3 | 0 | 3 | 6 | Intermediate |
| Liu, 2022 [69] | Case-Control | 3 | 0 | 3 | 6 | Intermediate |
| Restrepo, 2022 [22] | Case-Control | 1 | 0 | 3 | 4 | Intermediate |
| Babu, 2023 [70] | Case-Control | 3 | 0 | 2 | 5 | Intermediate |