Longterm effects of bile duct injuries on health-related quality of life: is a meta-analysis reliable?

Abstract

Sir, We read with great interest the paper published by Landman et al.1.Landman M.P. Feurer I.D. Moore D.E. Zaydfudim V. Pinson C.W. The longterm effect of bile duct injuries on health-related quality of life: a meta-analysis.HPB. 2012; 15: 252-259Abstract Full Text Full Text PDF Scopus (56) Google Scholar regarding health-related quality of life (HRQoL) in patients with bile duct injuries. We would like to raise three questions on the reliability of data derived from meta-analyses. Firstly, despite the methodological attempt to overcome heterogeneity through the standardization of effect sizes in this meta-analysis,1.Landman M.P. Feurer I.D. Moore D.E. Zaydfudim V. Pinson C.W. The longterm effect of bile duct injuries on health-related quality of life: a meta-analysis.HPB. 2012; 15: 252-259Abstract Full Text Full Text PDF Scopus (56) Google Scholar its HRQoL data are summarized from studies reporting on a wide spectrum of bile duct injuries, from bile leak to complete bile duct transection.2.Boerma D. Rauws E.A. Keulemans Y.C. Bergman J.J. Obertop H. Huibregtse K. et al.Impaired quality of life 5 years after bile duct injury during laparoscopic cholecystectomy: a prospective analysis.Ann Surg. 2001; 234: 750-757Crossref PubMed Scopus (193) Google Scholar, 3.de Reuver R.R. Sprangers M.A. Rauws E.A. Lameris J.S. Busch O.R. van Gulik T.M. et al.Impact of bile duct injury after laparoscopic cholecystectomy on quality of life: a longitudinal study after multidisciplinary treatment.Endoscopy. 2008; 40: 637-643Crossref PubMed Scopus (78) Google Scholar, 4.Melton G.B. Lillemoe K.D. Cameron J.L. Sauter P.A. Coleman J. Yeo C.J. Major bile duct injuries associated with laparoscopic cholecystectomy: effect of surgical repair on quality of life.Ann Surg. 2002; 235: 888-895Crossref PubMed Scopus (171) Google Scholar, 5.Hogan A.M. Hoti E. Winter D.C. Ridgway P.F. Maguire D. Geoghegan J.G. et al.Quality of life after iatrogenic bile duct injury: a case–control study.Ann Surg. 2009; 249: 292-295PubMed Google Scholar Heterogeneity in the type of bile duct injury may result in differences in HRQoL outcomes as diagnostic and therapeutic interventions vary depending on the complexity of the injury. Secondly, three of the studies included reported major patient losses (>15%), which makes it difficult to discern whether the inclusion of data for the missing patients might have changed the final results in these studies.3.de Reuver R.R. Sprangers M.A. Rauws E.A. Lameris J.S. Busch O.R. van Gulik T.M. et al.Impact of bile duct injury after laparoscopic cholecystectomy on quality of life: a longitudinal study after multidisciplinary treatment.Endoscopy. 2008; 40: 637-643Crossref PubMed Scopus (78) Google Scholar, 4.Melton G.B. Lillemoe K.D. Cameron J.L. Sauter P.A. Coleman J. Yeo C.J. Major bile duct injuries associated with laparoscopic cholecystectomy: effect of surgical repair on quality of life.Ann Surg. 2002; 235: 888-895Crossref PubMed Scopus (171) Google Scholar, 5.Hogan A.M. Hoti E. Winter D.C. Ridgway P.F. Maguire D. Geoghegan J.G. et al.Quality of life after iatrogenic bile duct injury: a case–control study.Ann Surg. 2009; 249: 292-295PubMed Google Scholar Finally, three studies were performed outside the USA.2.Boerma D. Rauws E.A. Keulemans Y.C. Bergman J.J. Obertop H. Huibregtse K. et al.Impaired quality of life 5 years after bile duct injury during laparoscopic cholecystectomy: a prospective analysis.Ann Surg. 2001; 234: 750-757Crossref PubMed Scopus (193) Google Scholar, 3.de Reuver R.R. Sprangers M.A. Rauws E.A. Lameris J.S. Busch O.R. van Gulik T.M. et al.Impact of bile duct injury after laparoscopic cholecystectomy on quality of life: a longitudinal study after multidisciplinary treatment.Endoscopy. 2008; 40: 637-643Crossref PubMed Scopus (78) Google Scholar, 5.Hogan A.M. Hoti E. Winter D.C. Ridgway P.F. Maguire D. Geoghegan J.G. et al.Quality of life after iatrogenic bile duct injury: a case–control study.Ann Surg. 2009; 249: 292-295PubMed Google Scholar How were the different population standards compared with the study results? Was a standardized USA HRQoL population norm used or were specific population norms considered? Although meta-analyses can derive important information from homogeneous observational and analytic studies, their results should be interpreted with caution when heterogeneity is not properly assessed. A single well-designed, observational study may be more accurate than a meta-analysis of several heterogeneous sources.