title: Reported effects in randomized controlled trials were compared with those of nonrandomized trials in cholecystectomy.
authors.affiliation: Institute for Research in Operative Medicine, University Witten/Herdecke, Cologne, Germany. dirkwmueller@gmx.de
authors.forename: Dirk
authors.initials: D
authors.lastname: Müeller
authors.forename: Stefan
authors.initials: S
authors.lastname: Sauerland
authors.forename: Edmund A M
authors.initials: EA
authors.lastname: Neugebauer
authors.forename: Marc
authors.initials: M
authors.lastname: Immenroth