ABSTRACT Background Clinical practice guidelines rely on expert panels to review evidence and develop recommendations. The traditional approach of engaging experts often relies on periodic full panel meetings which can lead to slow progress and variability in panel engagement. To address these issues, the ASCO introduced the Panel Subgroup (PSG) method, dividing panels into smaller working groups to enhance engagement, distribute workload, and accelerate guideline development. Objective To evaluate the PSG method on guideline development timelines, its uptake, perceived benefits, challenges, and lessons learned from the perspective of ASCO guideline methodologists. Methods This study had two phases. Phase 1 was a retrospective review of ASCO guideline administrative data (2017–2024) comparing guidelines developed using the traditional or PSG method. Guidelines were included if they were de novo, had over 50 included studies, and complete administrative records. Data extracted included number of panelists, research questions, studies reviewed, subgroups (for PSG), and development time. Phase 2 involved qualitative interviews with methodologists who used the PSG method to explore experiences, benefits, and challenges. Results Sixteen guidelines met the inclusion criteria: seven used the traditional method and nine used the PSG method. The average development time was 13 months (SD, 2.41) for the PSG method compared to traditional (23 months; SD, 6.30). PSG uptake among methodologists was 75% (6/8). Reported benefits included improved expert engagement, deeper evidence analysis, better collaboration, and shared authorship. Challenges included greater time demands, increased coordination, writing inconsistencies, and the need for full panel buy‐in. Conclusion The PSG method offers a promising structure to improve engagement and streamline productivity. While not without challenges, it may be particularly useful for large panels and complex guidelines when applied thoughtfully.
Summary What Is Already Known on This Topic: Clinical practice guidelines often involve large multidisciplinary expert panels that are prone to challenges of maintaining engagement and efficiency. Traditional approaches to guideline development often overburden co‐chairs and select members while leaving other panelists disengaged for extended periods. There are limited empirical evaluations of approaches to maintain expert panel engagement on guideline panels. What This Study Adds: The panel subgroup (PSG) method, which organizes expert panels into smaller working subgroups to streamline workflows, distribute responsibilities, and promote engagement of guideline panels. Evidence from ASCO's experience in using the PSG method shows that it enhances workflow efficiency by reducing guideline development delays and promoting steady progress through frequent subgroup meetings and communication. Methodologists observed improved panelist engagement and collaboration, as smaller groups enabled more thorough discussions and fostered professional connections among members. Challenges identified include harmonizing diverse writing styles, addressing duplicative efforts, ensuring subgroup expertise, and importance of early buy‐in from panelists. This study emphasizes critical skills required for successful implementation, including strong organizational, communication, and time‐management abilities. Key Takeaways: The PSG method provides a promising framework for improving guideline development by fostering collaboration, increasing efficiency, and promoting sustained engagement.