The current EPIC-lung study, including selection criteria, has also been described in detail previously (18,21,22). The study included lung cancer cases diagnosed on average 62 months, and a minimum 1 of month, after blood collection together with matching controls from eight of the ten participating countries: France, Italy, Spain, United Kingdom, The Netherlands, Greece, Germany and Sweden (excluding the Malmö centre). Where possible, two controls were matched to each case by study center, gender, date of blood collection (± 1 month, relaxed to ± 5 months for sets without available controls), and date of birth (± 1 year, relaxed to ± 5 years for sets without available controls). Overall, 894 cases and 1805 controls were included in the analysis (Table 1). Information on tobacco consumption was collected in a non-dietary questionnaire as a part of the recruitment procedure in the EPIC cohort. Study participants were classified as never, current or ex-smokers. Duration of smoking was calculated based on collected information on age of smoking initiation and age at recruitment for current smokers or age at smoking cessation for ex-smokers. Additionally,
