We therefore conducted a case-control study with 515 incident lung cancer cases and 1030 age- and sex-matched controls without cancer , and further conducted a meta-analysis .
O O O O O O O O O B-DiseaseOrPhenotypicFeature I-DiseaseOrPhenotypicFeature O O O O O O O O B-DiseaseOrPhenotypicFeature O O O O O O O