AGREE-S: AGREE II extension for surgical interventions: appraisal instrument

Background: The Appraisal of Guidelines Research and Evaluation (AGREE) II instrument was developed to evaluate the quality of clinical practice guidelines. Evidence suggests that development, reporting, and appraisal of guidelines on surgical interventions may be better informed by modification of the instrument. Objective: We aimed to develop an AGREE II extension specifically designed for appraisal of guidelines of surgical interventions. Methods: In a three-part project funded by the United European Gastroenterology and the European Association for Endoscopic Surgery, (i) we identified factors that were associated with higher quality of surgical guidelines, (ii) we statistically calibrated the AGREE II instrument in the context of surgical guidelines using correlation, reliability, and factor analysis, and (iii) we undertook a Delphi consensus process of stakeholders to inform the development of an AGREE II extension instrument for surgical interventions. Results: Several features were prioritized by stakeholders as of particular importance for guidelines of surgical interventions, including development of a guideline protocol, consideration of practice variability and surgical expertise in different settings, and specification of infrastructures required to implement the recommendations. The AGREE-S—AGREE II extension instrument for surgical interventions has 25 items, compared to the 23 items of the original AGREE II instrument, organized into the following 6 domains: Scope and purpose, Stakeholders, Evidence synthesis, Development of recommendations, Editorial independence, and Implementation and update. As the original instrument, it concludes with an overall appraisal of the quality of the guideline and a judgement on whether the guideline is recommended for use. Several items were amended and rearranged among domains, and an item was deleted. The Rigor of Development domain of the original AGREE II was divided into Evidence Synthesis and Development of Recommendations. Items of the AGREE II domain Clarity of Presentation were incorporated in the new domain Development of Recommendations. Three new items were introduced, addressing the development of a guideline protocol, support by a guideline methodologist, and consideration of surgical experience/expertise. Conclusion: The AGREE-S appraisal instrument has been developed to be used for assessment of the methodological and reporting quality of guidelines on surgical interventions.