Firdha Mahrifatul Zana, Cholis Sa'dijah, Susiswo, Lathiful Anwar, Hutkemri Zulnaidi
This research and development (R&D) is an effort to develop and evaluate the quality of an assessment instrument based on the alignment of students' cognitive skills on the topic of Trigonometric Comparisons in Right Triangles to measure critical thinking skills. The Zulkardis' modified model consisting of four stages was used to support the development of assessment instruments. These four stages are divided into two phases, namely the preliminary and prototyping stages where the researchers prepare and develop the main instrument, then the formative evaluation and field test stage where the researchers assess the validity and reliability. The assessment instruments developed are three main problems at the Evaluating level with each assessment containing two to three sub-problems that assess: critiquing, checking, monitoring, and judging. There are two analysis results related to validity: the content validity index (I-CVI) and the content validation value per scale (S-CVI). The findings show that the I-CVI value ranges from 0.87 to 1.00 while the S-CVI/Average value is 0.93. These results indicate that the instrument has an acceptable level of validity. The reliability test assisted by ANATES 4.00 software also shows that the accuracy level of instrument items has reached an Alpha Coefficient of 0.82 and a Reliability of 0.90. Apart from that, the field test findings also show the discrimination index value of between 45% and 65%, where this index shows the test's ability to differentiate the skills of the students being tested and the difficulty level index value between 60% and 70% for each question item, which shows the proportion of students who were able to answer the question item correctly. These results indicate that each item has a moderate difficulty level with good discriminating power so that it can be used repeatedly to measure students' critical thinking skills. This research and development provide innovations for teachers to prepare assessments by paying attention to two dimensions, namely cognitive and knowledge therefore it can be ensured that the assessment correctly measures the skills desired by the curriculum outcomes. © 2025 American Institute of Physics Inc.. All rights reserved.
Departement ofMathematics, Universitas Negeri Malang, Malang City, Indonesia; Departement ofMathematics and Science Education, Universiti Malaya, Kuala Lumpur, Malaysia
