. 2022 Dec 1;276(6):1047-1055.

doi: 10.1097/SLA.0000000000004707. Epub 2020 Dec 29.

International Core Outcome Set for Acute Simple Appendicitis in Children: Results of a Systematic Review, Delphi Study, and Focus Croups With Young People

Max Knaapen¹, Nigel J Hall², Darcy Moulin³, Johanna H van der Lee^{4

5}, Nancy J Butcher⁶, Peter C Minneci⁷, Jan F Svensson⁸, Shawn D St Peter⁹, Susan Adams¹⁰, Shireen A Nah^{11

12}, Erik D Skarsgard¹³, Augusto Zani^{14

15}, Sherif Emil¹⁶, Janne S Suominen¹⁶, Dayang A Aziz¹⁷, Rambha Rai¹¹, Martin Offringa^{16

18}, Ernst W van Heurn¹, Roel Bakx¹, Ramon R Gorter¹; pediatric appendicitis COS development group

Affiliations

¹ Department of Pediatric Surgery, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam & Vrije Universiteit, Amsterdam, The Netherlands.
² University Surgery Unit, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK; Department of Paediatric Surgery and Urology, Southampton Children's Hospital, Southampton, UK.
³ Parent and Patient Representative, New Albany, Ohio.
⁴ Pediatric Clinical Research Office, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
⁵ Knowledge Institute of the Dutch Association of Medical Specialists, Utrecht, The Netherlands.
⁶ Child Health Evaluative Sciences, The Hospital for Sick Children Research Institute, Toronto, Canada.
⁷ Center for Surgical Outcomes Research, Abigail Wexner Research Institute and Department of Surgery, Nationwide Children's Hospital, Columbus, Ohio.
⁸ Department of Pediatric Surgery, Karolinska University Hospital, Stockholm, Sweden; Department of Women's and Children's Health, Karolinska Institute, Stockholm, Sweden.
⁹ Department of Surgery, Children's Mercy Hospital, Kansas City, Missouri.
¹⁰ Department of Pediatric Surgery, Sydney Children's Hospital, Randwick, NSW, Australia; School of Women's and Children's Health, University of New South Wales, NSW, Australia.
¹¹ Department of Pediatric Surgery, KK Women's and Children's Hospital, Singapore, Singapore.
¹² Division of Paediatric Surgery, Department of Surgery, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
¹³ Department of Pediatric Surgery, British Columbia Children's Hospital, Vancouver, BC, Canada.
¹⁴ Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON, Canada.
¹⁵ Department of Surgery, University of Toronto, Toronto, ON, Canada; §§§Harvey E. Beardmore Division of Pediatric Surgery, Montreal Children's Hospital, Montreal, QC, Canada.
¹⁶ Department of Pediatric Surgery, Helsinki Children's Hospital, Helsinki, Finland.
¹⁷ Department of Pediatric Surgery, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia.
¹⁸ Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Canada.

PMID: 33630468
PMCID: PMC9645539
DOI: 10.1097/SLA.0000000000004707

International Core Outcome Set for Acute Simple Appendicitis in Children: Results of a Systematic Review, Delphi Study, and Focus Croups With Young People

Max Knaapen et al. Ann Surg. 2022.

. 2022 Dec 1;276(6):1047-1055.

doi: 10.1097/SLA.0000000000004707. Epub 2020 Dec 29.

Authors

Affiliations

¹ Department of Pediatric Surgery, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam & Vrije Universiteit, Amsterdam, The Netherlands.
² University Surgery Unit, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK; Department of Paediatric Surgery and Urology, Southampton Children's Hospital, Southampton, UK.
³ Parent and Patient Representative, New Albany, Ohio.
⁴ Pediatric Clinical Research Office, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
⁵ Knowledge Institute of the Dutch Association of Medical Specialists, Utrecht, The Netherlands.
⁶ Child Health Evaluative Sciences, The Hospital for Sick Children Research Institute, Toronto, Canada.
⁷ Center for Surgical Outcomes Research, Abigail Wexner Research Institute and Department of Surgery, Nationwide Children's Hospital, Columbus, Ohio.
⁸ Department of Pediatric Surgery, Karolinska University Hospital, Stockholm, Sweden; Department of Women's and Children's Health, Karolinska Institute, Stockholm, Sweden.
⁹ Department of Surgery, Children's Mercy Hospital, Kansas City, Missouri.
¹⁰ Department of Pediatric Surgery, Sydney Children's Hospital, Randwick, NSW, Australia; School of Women's and Children's Health, University of New South Wales, NSW, Australia.
¹¹ Department of Pediatric Surgery, KK Women's and Children's Hospital, Singapore, Singapore.
¹² Division of Paediatric Surgery, Department of Surgery, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
¹³ Department of Pediatric Surgery, British Columbia Children's Hospital, Vancouver, BC, Canada.
¹⁴ Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON, Canada.
¹⁵ Department of Surgery, University of Toronto, Toronto, ON, Canada; §§§Harvey E. Beardmore Division of Pediatric Surgery, Montreal Children's Hospital, Montreal, QC, Canada.
¹⁶ Department of Pediatric Surgery, Helsinki Children's Hospital, Helsinki, Finland.
¹⁷ Department of Pediatric Surgery, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia.
¹⁸ Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Canada.

PMID: 33630468
PMCID: PMC9645539
DOI: 10.1097/SLA.0000000000004707

Abstract

Objective: To develop an international core outcome set (COS), a minimal collection of outcomes that should be measured and reported in all future clinical trials evaluating treatments of acute simple appendicitis in children.

Summary of background data: A previous systematic review identified 115 outcomes in 60 trials and systematic reviews evaluating treatments for children with appendicitis, suggesting the need for a COS.

Methods: The development process consisted of 4 phases: (1) an updated systematic review identifying all previously reported outcomes, (2) a 2-stage international Delphi study in which parents with their children and surgeons rated these outcomes for inclusion in the COS, (3) focus groups with young people to identify missing outcomes, and (4) international expert meetings to ratify the final COS.

Results: The systematic review identified 129 outcomes which were mapped to 43 unique outcome terms for the Delphi survey. The first-round included 137 parents (8 countries) and 245 surgeons (10 countries), the second-round response rates were 61% and 85% respectively, with 10 outcomes emerging with consensus. After 2 young peoples' focus groups, 2 additional outcomes were added to the final COS (12): mortality, bowel obstruction, intraabdominal abscess, recurrent appendicitis, complicated appendicitis, return to baseline health, readmission, reoperation, unplanned appendectomy, adverse events related to treatment, major and minor complications.

Conclusion: An evidence-informed COS based on international consensus, including patients and parents has been developed. This COS is recommended for all future studies evaluating treatment ofsimple appendicitis in children, to reduce heterogeneity between studies and facilitate data synthesis and evidence-based decision-making.

PubMed Disclaimer

Conflict of interest statement

The authors report no conflicts of interest.

Figures

**Figure 1**
Schematic depiction of outcome term identification from SRs. RCTs indicates randomized controlled trials; SRs, systematic reviews.

See this image and copyright information in PMC

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International Core Outcome Set for Acute Simple Appendicitis in Children: Results of a Systematic Review, Delphi Study, and Focus Croups With Young People

Affiliations

International Core Outcome Set for Acute Simple Appendicitis in Children: Results of a Systematic Review, Delphi Study, and Focus Croups With Young People

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