Quality assessment of cancer cachexia clinical practice guidelines

Objectives: The aim of this study was to investigate the quality of clinical practice guidelines of cancer cachexia and identifying gaps limiting knowledge. Methods: A systematic search of relevant guideline websites and literature databases (including PubMed, NCCN, NGC, SIGN, NICE, and google) was undertaken from inception to March 2017 to identify and select clinical guidelines related to cancer cachexia. Four independent reviewers assessed the eligible guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument. Agreement among reviewers of the guidelines was measured by using intra-class correlation coefficient (ICC). The number of recommendations, strength of recommendation, and levels of evidence were determined. Results: Nine cancer cachexia guidelines published from 2006 to 2017 were identified. An overall high degree of agreement among reviewers to each domain was observed (ICC ranged from 0.75 to 0.91). The median scores and range for each AGREE II domain were as follows: (i) scope and purpose (median = 61.1%, range: 13.9% to 80.7%); (ii) stakeholder involvement (median = 26.4%, range: 8.3% to 81.9%); (iii) rigour of development (median = 35.9%, range: 3.6% to 84.4%); (iv) clarity and presentation (median = 56.9%, range: 30.6% to 76.4%); (v) applicability (median = 19.8%, range: 0% to 77.1%) and (vi) editorial independence (median = 27.1%, range: 0% to 85.4%). Two cancer cachexia guidelines (ESPEN, 2017 and University of Queensland, 2013) scored higher on all domains and were classified as recommended for clinical practice, among which, one was developed by European Society for Parenteral and Enteral Nutrition and European Partnership for Action Against Cancer, and the other was developed by University of Queensland. In addition, more than a half recommendations were based on nonrandomized studies (Level C, 50.0%) and expert opinion (Level D, 8.2%). Conclusions: The quality of cancer cachexia guidelines was highly heterogeneous among different domains even within the same guideline. There is significant room for improvement to develop high quality cancer cachexia guidelines, which urgently warrants first-class research to minimize the vital gaps in the evidence for formulation of cancer cachexia guidelines.