Additional file 9: of Smoking influences the need for surgery in patients with the inflammatory bowel diseases: a systematic review and meta-analysis incorporating disease duration KuenzigM. LeeSang EksteenBertus SeowCynthia BarnabeCheryl PanaccioneRemo KaplanGilaad 2016 Raw study Data. Excel file containing hazard ratios from individual studies included in the meta-analysis. (XLSX 45 kb)