title: Improving GRADE evidence tables part 2: a systematic survey of explanatory notes shows more guidance is needed.
abstract: The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group has developed GRADE evidence profiles (EP) and summary of findings (SoF) tables to present evidence summaries in systematic reviews, clinical guidelines, and health technology assessments. Explanatory notes are used to explain choices and judgments in these summaries, for example, on rating of the quality of evidence.
  
  
  
  A systematic survey of the explanations in SoF tables in 132 randomly selected Cochrane Intervention reviews and in EPs of 10 guidelines. We analyzed the content of 1,291 explanations using a predefined list of criteria.
  
  
  
  Most explanations were used to describe or communicate results and to explain downgrading of the quality of evidence, in particular for risk of bias and imprecision. Addressing the source of baseline risk (observational data or control group risk) was often missing. For judgments about downgrading the quality of evidence, the percentage of informative explanations ranged between 41% (imprecision) and 79% (indirectness).
  
  
  
  We found that by and large explanations were informative but detected several areas for improvement (e.g., source of baseline risk and judgments on imprecision). Guidance about explanatory footnotes and comments will be provided in the last article in this series.
authors.affiliation: Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academic Medical Center, University of Amsterdam, PO Box 22660, J1B-211, 1100 DD Amsterdam, The Netherlands.
authors.forename: Miranda
authors.initials: M
authors.lastname: Langendam
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada; Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Universidad de Chile, Sergio Livingstone Pohlhammer 943, Independencia, Santiago, Chile; Evidence-Based Dentistry Unit, Faculty of Dentistry, Universidad de Chile, Sergio Livingstone Pohlhammer 943, Independencia, Santiago, Chile.
authors.forename: Alonso
authors.initials: A
authors.lastname: Carrasco-Labra
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
authors.forename: Nancy
authors.initials: N
authors.lastname: Santesso
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada; Department of Medicine, University of Missouri, 2411 Holmes St., Kansas City, MO 64108-2792, USA; Department of Biomedical and Health Informatics, University of Missouri, 2411 Holmes St., Kansas City, MO 64108-2792, USA.
authors.forename: Reem A
authors.initials: RA
authors.lastname: Mustafa
authors.affiliation: Evidence-Based Dentistry Unit, Faculty of Dentistry, Universidad de Chile, Sergio Livingstone Pohlhammer 943, Independencia, Santiago, Chile; Institute of Health Policy, Management and Evaluation, University of Toronto, 155 College St, 4th Floor, Toronto, Ontario M5T 3M6, Canada.
authors.forename: Romina
authors.initials: R
authors.lastname: Brignardello-Petersen
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: Ventresca
authors.affiliation: Dutch Cochrane Centre, Julius Center-UMC Utrecht, Huispostnummer Str. 6.131, Postbus 85500, 3508 GA Utrecht.
authors.forename: Pauline
authors.initials: P
authors.lastname: Heus
authors.affiliation: Cochrane Editorial Unit, St Albans House, 57-59 Haymarket, London SW1Y 4QX, United Kingdom.
authors.forename: Toby
authors.initials: T
authors.lastname: Lasserson
authors.affiliation: Nordic Cochrane Centre, Blegdamsvej 9, 7811, 2100 Copenhagen, Denmark.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Moustgaard
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada; Department of Medicine, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
authors.forename: Jan
authors.initials: J
authors.lastname: Brozek
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada; Department of Medicine, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada; Cochrane Applicability and Recommendations Methods Group, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada; McMaster GRADE Center, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada. Electronic address: schuneh@mcmaster.ca.
authors.forename: Holger J
authors.initials: HJ
authors.lastname: Schünemann
mesh_terms: D019317:Evidence-Based Medicine; D017408:Guidelines as Topic / Q000592:standards; D006801:Humans; D033181:Information Dissemination / Q000379:methods*; D007600:Judgment; D058028:Research Report / Q000592:standards*; D012196:Review Literature as Topic; D013673:Technology Assessment, Biomedical / Q000592:standards
keywords: GRADE; GRADEpro; Health technology assessment; Quality of evidence; Risk of bias; Summary of findings tables; Systematic reviews