Are IFRS-based and US GAAP-based accounting amounts comparable?

► Accounting system and value relevance comparability with US firms is greater when IFRS firms apply IFRS. ► Comparability is greater for mandatory adopters, for firms in common law and high enforcement countries, and recent years. ► Earnings smoothing, accrual quality, and timeliness are potential sources of the greater comparability. ► Widespread application of IFRS has enhanced financial reporting comparability, but differences remain.