BACKGROUND:The objective of this study was to describe the implementation of comprehensive geriatric assessment (CGA) in clinical trials dedicated to older patients before and after the creation of the International Society of Geriatric Oncology in the early 2000s. SUBJECTS, MATERIALS, AND METHODS:All phase I, II, and III trials dedicated to the treatment of cancer among older patients published between 2001 and 2004 and between 2011 and 2014 were reviewed. We considered that a CGA was performed when the authors indicated an intention to do so in the Methods section of the article. We collected each geriatric domain assessed using a validated tool even in the absence of a clear CGA, including nutritional, functional, cognitive, and psychological status, comorbidity, comedication, overmedication, social status and support, and geriatric syndromes. RESULTS:A total of 260 clinical trials dedicated to older patients were identified over the two time periods: 27 phase I, 193 phase II, and 40 phase III trials. CGA was used in 9% and 8% of phase II and III trials, respectively; it was never used in phase I trials. Performance status was reported in 67%, 79%, and 75% of phase I, II, and III trials, respectively. Functional assessment was reported in 4%, 11%, and 13% of phase I, II, and III trials, respectively. Between the two time periods, use of CGA increased from 1% to 11% (p = .0051) and assessment of functional status increased from 3% to 14% (p = .0094). CONCLUSION:The use of CGA in trials dedicated to older patients increased significantly but remained insufficient. IMPLICATIONS FOR PRACTICE:This article identifies the areas in which research efforts should be focused in order to offer physicians well-addressed clinical trials with results that can be extrapolated to daily practice.