Quality parameters | Score | ||
---|---|---|---|
2 | 1 | 0 | |
Population sample | > 100 | 50–100 | < 50 |
Study design | Case and control group were both selected from hospital | Control groups were selected from normal residents | Unknown |
General informationa | Complete | Partial | Inadequate |
Matching of case group and control group | > 3 factors | 1–3 factors | None |
Detection methods | Multiplex PCR | PCR–RFLP | Other methods |