Improvement was needed in the standards of development for cancer core outcome sets

Objective: The Core Outcome Set-STAndards for Development (COS-STAD) contains 11 standards (12 criteria) that are deemed to be the minimum design recommendations for all core outcome set (COS) development projects. Cancer is currently the disease area with the highest number of published COSs and is a major cause of worldwide morbidity and mortality. The aim of this study was to provide a baseline of cancer COS standards. Study Design and Setting: Systematic reviews of COSs have identified 307 published COS studies. Cancer COSs were eligible for inclusion. Two reviewers independently assessed each of the COSs against the 12 criteria. Results: Forty-nine cancer COSs were included; none met all 12 criteria representing the 11 minimum standards assessed in this study (range = 4-11 criteria, median = 6 criteria). All studies met the four scope standards, eight (16%) met all three standards for stakeholders involved, and two (4%) met all four standards for consensus process standards. Conclusion: With the exception of "scope" specification, there is much need for improvement. Poor reporting often made it challenging to assess whether minimum standards were met. The consensus process criteria were most difficult to assess, particularly those that required an assessment of being a priori. This is the first application of COS-STAD criteria to studies that have developed COSs and provides a baseline of cancer COS standards of development. (C) 2019 The Authors. Published by Elsevier Inc.