In both the mathematics and science assessments, items vary in terms of item format (see the table below) and item difficulty. They also differ across grade levels to reflect the nature, difficulty, and emphasis of the subject matter encountered in school at each grade.
Table B. Percentage of TIMSS mathematics and science assessment score points, by grade and item format: 2015
|Grade 4||Grade 8||Grade 4||Grade 8|
|NOTE: The percentages in this table are based on the number of score points, not the number of items. The number of score points and the number of items are not the same because some constructed-response items are worth more than one score point. (For the corresponding percentages based on the number of items, see the Methodology and Technical Notes. Multiple-choice items require students to select the single correct response from four response options. Constructed-response items require students to generate a written response.
SOURCE: Martin, M.O., Mullis, I.V.S., and Hooper, M. (Eds.). (2016). Methods and Procedures in TIMSS 2015. Chestnut Hill, MA: TIMSS & PIRLS International Study Center, Boston College.