AGREE II tool  
We used the AGREE II tool to assess the quality of the CPGs development. (6) AGREE II is a validated instrument composed of 23 items grouped under 6 domains and one final item to evaluate the overall quality of the CPG. The domains are: Scope and Purpose (3 items), Stakeholder Involvement (3 items), Rigor of Development (8 items), Clarity of Presentation (3 items), Applicability (4 items), and Editorial Independence (4 items). For each item, each appraiser is asked to score based on the statement, using a Likert scale from 1 ((Strongly disagree) to 7 (Strongly agree). A score between 2 and 6 is assigned when the reporting of the AGREE II item does not meet the full criteria or considerations depending on the completeness and quality of reporting. Scores increase as more criteria are met and considerations addressed.(5, 14, 15)
Following the recommendations by the AGREE collaboration, each CPG was evaluated independently by three assessors. With the aim of reducing the variability among the assessors we performed an intensive training in the tool led by one of the investigators (IDF), expert in the use of AGREE II. After initial training, the assessors were calibrated by independently assessing two CPGs (one low quality and one high quality), followed by feedback from the trainer (IDF), and by a group discussion to solve any issues that arose.
We performed two rounds of assessment and feedback. We considered disagreement between the assessors when the differences among the scores were of 3 or more points, and they were resolved by discussion. If agreement was not achieved after the discussion, two reviewers (IDF, LEC) made the final assessment and decision. Final scores per domain were calculated by summing up scores from the 3 assessors per individual item in a domain and by scaling the total as a percentage of the maximum possible score for that domain. Therefore, each domain was scored in a range from 0 to 100%.
The AGREE collaboration does not define minimum domain scores or patterns of scores across domains to differentiate between high quality and poor-quality guidelines. (20)  Instead, the recommendation for users is to use the scores to compare CPG among them and determine specific thresholds based on the context in which the guidelines are to be used. All the assessment were performed using the My AGREE-PLUS online tool provided by the AGREE collaboration (http://www.agreetrust.org/resource-centre/agree-plus/).