This scoping review identified what kinds of work disability policy issues are critiqued in articles published in countries with cause-based versus comprehensive welfare systems. Drawing on a review of work disability policy research, we identified 74 English-language, peer-reviewed articles that focused on program adequacy and design. Articles on cause-based systems dwelled on system fairness and policies of proof of entitlement, while those on comprehensive systems focused more on system design complexities relating to worker inclusion and scope of medical certificates. Overall, we observed a clear difference in the nature of problems examined in the different systems. Gaps in work disability policy literature are identified, and challenges for comparative policy research are discussed.