The principle of comparability must be based on the principles of consistency and objectivity. Only when the accounting information of the same accounting entity is consistent in the accounting period can the comparison between different accounting entities be useful; Only when the accounting information of each accounting entity is true, reliable and comparable can the comparison between them be relevant and useful.
Relevant or reliable accounting information is not necessarily comparable accounting information. In order to increase comparability, different accounting entities should adopt unified accounting methods and procedures as far as possible, and take accounting standards or accounting systems as norms. However, overemphasizing the unification of accounting methods and procedures and pursuing comparability may weaken or even destroy the relevance and reliability. If the unity conceals the real differences between accounting entities, its comparability will be greatly weakened.
The principle of comparability requires the accounting entity to prompt the accounting methods and procedures it adopts, and to disclose the changes, reasons and their impact on the financial position and operating performance when changing the accounting methods and procedures.