Table 3.
Quality assessment of case control studies using New Castle Ottawa Scale
| First author | Selection | Comparability | Exposure | ||||||
|---|---|---|---|---|---|---|---|---|---|
|
|
|
|
|||||||
| Case definition is adequate | Consecutive or obviously representative series of cases | Community controls | No history of disease (endpoint) in controls | Study controls for the most important factor | Study controls for any additional factor | Secure record/structured interview blind to case/control status | Same method for ascertainment for cases and controls | Nonresponse rate same for both groups | |
| Hiraki, 2008[22] | - | * | - | * | * | * | - | * | - |
| Mai, 2014[26] | * | * | - | - | - | * | - | * | - |
| Chrysanthakopoulos, 2016[28] | * | * | * | * | * | * | * | * | - |
| Yoon, 2019[32] | - | * | * | * | - | * | - | - | * |
*Significant and -nonsignificant