Systematic review of grading systems for adverse surgical outcomes

Systematic review of grading systems for adverse surgical outcomes

Can J Surg 2020;64(2):E196-E204 | PDF | Appendix 1 | Appendix 2

Saba Balvardi, MD; Etienne St-Louis, MD; Yasmine Yousef, MD; Asra Toobaie, MD; Elena Guadagno, MLIS; Robert Baird, MD; Dan Poenaru, MD


Background: Grading scales for adverse surgical outcomes have been poorly characterized to date. The primary aim of this study was to conduct a systematic review to enumerate the various frameworks for grading adverse postoperative outcomes; our secondary objective was to outline the properties of each grading system, identifying its strengths and weaknesses.

Methods: We searched 9 databases (Africa Wide Information, Biosis, Cochrane, Embase, Global Health, LILACs, Medline, PubMed and Web of Science) from 1992 (the year the Clavien–Dindo classification system was developed) until Mar. 2, 2017, for studies that aimed to develop or improve on an already existing generalizable system for grading adverse postoperative outcomes. Study selection was duplicated as per PRISMA recommendations. Procedure-specific grading systems were excluded. We assessed the framework, strengths and weaknesses of the systems qualitatively.

Results: We identified 9 studies on 8 adverse outcome grading systems with frameworks generalizable to any surgical procedure. Most systems have not been widely incorporated in the literature. Seven of the 8 systems were produced without including patients’ perspectives. Four allowed the derivation of a composite morbidity score, which had limited tangible significance for patients.

Conclusion: Although each instrument identified offered its own advantages, none satisfied the need for a patient-centred tool capable of generating a composite score of all possible postoperative adverse outcomes (complications, sequelae and failure) that enables comparison of noninterventional and surgical management of disease. There is a need for development of a more comprehensive, patient-centred grading system for adverse postoperative outcomes.


Contexte : Jusqu’ici, les systèmes de classification des issues postopératoires indésirables n’ont pas encore fait l’objet d’une analyse comparative. Cette étude avait pour objectif principal de recenser, au moyen d’une revue systématique de la littérature, les divers systèmes de classification des issues postopératoire indésirables, et pour objectif secondaire de dégager les propriétés, les forces et les faiblesses de chaque système.

Méthodes : Nous avons interrogé 9 bases de données (Africa Wide Information, Biosis Previews, Cochrane, Embase, Global Health, LILACS, Medline, PubMed et Web of Science) pour trouver des articles publiés entre 1992 (année de la mise au point du système de classification de Clavien–Dindo) et le 2 mars 2017. Ces articles devaient porter sur la création d’un système généralisable de classification des issues postopératoires indésirables, ou l’amélioration d’un système existant. La sélection des études a été faite en double, conformément aux recommandations PRISMA. Les systèmes de classification visant une seule intervention ont été exclus. Nous avons évalué, d’un point de vue qualitatif, le cadre, les forces et les faiblesses des systèmes retenus.

Résultats : Nous avons retenu 9 études sur 8 systèmes de classification accompagnés d’un cadre pouvant être appliqué à n’importe quelle intervention chirurgicale. La plupart des systèmes n’avaient pas été largement étudiés. Sept des 8 systèmes avaient été développés sans tenir compte du point de vue des patients, et 4 permettaient de calculer un score de morbidité composite ayant des retombées concrètes limitées pour les patients.

Conclusion : Tous les systèmes retenus s’accompagnaient d’avantages, mais aucun ne pouvait servir d’outil centré sur le patient permettant de calculer un score composite pour toutes les issues postopératoires possibles (complications, séquelles et échec), score qui pourrait servir à comparer les prises en charge conservatrice et chirurgicale des maladies. La création d’un système de classification des issues postopératoires indésirables exhaustif centré sur le patient est nécessaire.

Presented at the Canadian Surgical Forum 2018, Sept. 13–15, 2018, St. John’s, Nfld.

Accepted May 5, 2020

Affiliations: From the Division of Paediatric General and Thoracic Surgery, McGill University, Montréal, Que. (Balvardi, St-Louis, Yousef, Toobaie, Poenaru); the McConnell Resource Centre, McGill University Health Centre, Montréal, Que. (Guadagno); and the Division of Pediatric General Surgery, University of British Columbia, Vancouver, BC (Baird).

Competing interests: None declared.

Contributors: All the authors designed the study. S. Balvardi and E. Guadagno acquired the data, which S. Balvardi and D. Poenaru analyzed. S. Balvardi wrote the article, which all authors critically revised. All authors gave final approval of the article to be published.

Content licence: This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BYNCND 4.0) licence, which permits use, distribution and reproduction in any medium, provided that the original publication is properly cited, the use is noncommercial (i.e., research or educational use), and no modifications or adaptations are made. See:

Funding: No funding was received for this work.

DOI: 10.1503/cjs.016919

Correspondence to: D. Poenaru, McGill University Health Centre, B04.2022.2−1001 Décarie Blvd, Montréal QC H4A 3J1,