Epidemiology of perforating peptic ulcer: A population-based retrospective study over 40 years
Aydin Dadfar, Tom-Harald Edna, Department of Surgery, Levanger Hospital, Nord-Trøndelag Hospital Trust, Levanger 7600, Norway
Tom-Harald Edna, Institute of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim 7491, Norway
Author contributions: Dadfar A made substantial contributions to the conception and design of the study, acquisition, analysis, and interpretation of data, and drafting the article; Edna TH made substantial contributions to the conception and design of the study, acquisition, analysis, and interpretation of data, and drafting the article; all authors read and approved the final manuscript.
Institutional review board statement: This study was reviewed and approved by the Levanger Hospital Institutional Review Board Committee on Human Rights Related to Research Involving Human Subjects (2018/2760 – 33974/2018).
Informed consent statement: Not necessary according to the Regional Committee for Medical and Health Research Ethics (REC), Helse Midt (2018/1510).
Conflict-of-interest statement: The authors declare the absence of conflicts of interest.
Data sharing statement: No additional data are available.
STROBE statement: The authors have read the STROBE Statement – checklist of items, and the manuscript was prepared and revised according to the STROBE Statement.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Aydin Dadfar, MD, Surgeon, Department of Surgery, Levanger Hospital, Nord-Trøndelag Hospital Trust, Kirkegata 2, Levanger 7600, Norway. email@example.com
Received: March 24, 2020
Peer-review started: March 24, 2020
First decision: April 25, 2020
Revised: June 23, 2020
Accepted: August 29, 2020
Article in press: August 29, 2020
Published online: September 21, 2020