From: Current evidences on XPC polymorphisms and gastric cancer susceptibility: a meta-analysis
Criteria | Score |
---|---|
Representativeness of cases | |
Selected from cancer registry or multiple cancer center sites | 2 |
Selected from oncology department or cancer institute | 1 |
Selected without clearly defined sampling frame or with extensive inclusion/exclusion criteria | 0 |
Source of controls | |
Population or community based | 2 |
Both population-based and hospital-based/healthy volunteers/blood donors | 1.5 |
Hospital-based controls without gastric cancer | 1 |
Cancer-free controls without total description | 0.5 |
Not described | 0 |
Ascertainment of gastric cancer | |
Histologically or pathologically confirmed | 2 |
Diagnosis of gastric cancer by patient medical record | 1 |
Not described | 0 |
Sample size | |
>1000 | 2 |
200-1000 | 1 |
<200 | 0 |
Quality control of genotyping methods | |
Clearly described a different genotyping assay to confirm the data | 1 |
Not described | 0 |
Hardy-Weinberg equilibrium | |
Hardy-Weinberg equilibrium in controls | 1 |
Hardy-Weinberg disequilibrium in controls | 0.5 |
No checking for Hardy-Weinberg disequilibrium | 0 |