Additional file 2: of Study protocol of the German Study on Tobacco Use (DEBRA): a national household survey of smoking behaviour and cessation KastaunSabrina BrownJamie BroseLeonie RatschenElena RaupachTobias NowakDennis Cholmakow-BodechtelConstanze ShahabLion WestRobert KotzDaniel 2017 DEBRA - Follow-up survey. (DOCX 38 kb)