In drawing up level descriptions, designing test tasks, testing, and scoring, the TOP has been standardized and developed under strict scrutiny of researchers and scholars in the field of linguistics, and language teaching and testing.

The authentic materials used in the TOP are extracted from materials in daily life, such as advertisements, public announcements, notices, letters, memos, time schedules, and weather broadcasts. In addition, these diversified texts are derived from a variety of fields, including literature, science, art, astronomy, and history.