Test construction is based upon practical and scientific rules that are applied before, during and after each item until it finally becomes a part of the test. The following are the stages of constructing a test as followed by the Center.
Each year the Center attracts a number of competent specialists in testing and educationalists to attend in workshops that deal with the theoretical and applied aspects of the test.
The theoretical aspects include:
- the concepts on which a test is constructed
- the goals and objectives of the test.
- the general components , parts and sections of a test
- the theoretical and technical foundations to write test items.
The applied training includes:
- discussing different types of test items. This aims at putting theoretical and technical concepts into practice.
- collective training on writing items for various parts of the test
- constructing items on individual basis (outside workshops) which is intended as peer teaching.
- Each item's writer is charged with making questions that are relevant to his/her specialty.
- Each item's writer is given a code number that carries his/her personal data for confidentiality.
- Each item is given a code number that is kept intact. Each item is in the question bank even if it is not to be used in the test.
Various items of the test are referred by a 3-member committee:
- a specialist in the content area.
- a specialist in measurement
- an experienced educator.
Each item is either:
- accepted as is, or
- accepted after modifications, or
- rejected as invalid.
Based on a set questionnaire the committee judge each item from various dimensions including the nature of the item, item difficulty, item conformity to the content controls, item bias, and item quality. Justifications have to be provided if an item is deemed invalid. All data is entered into the Center's computer.
All items are entered into the computer marked with the relevant judgment except those deemed invalid.
All the computerized items are reviewed by four testing experts to verify:
- strict implementation of referring committee comments.
- accuracy of numbers and graphs.
- no grammatical, spelling errors or misprints.
- full compliance to items with the test pre-set standards and regulations.
- answer key is provided for all test items.
- screening out the items that seem too complicated or might take too much time to answer.
Item Trial (pilot testing )
Trial items are included in the actual test and they go through the same stages of test preparation above, but they do not calculate towards the final score.
Items are statistically analyzed so that the valid ones are selected for the test, while the invalid ones are rejected.
Test is constructed in its final form. Items are randomly selected from those deposited in the question bank in a manner that adequately represents that various parts of test dimensions.
The test is finally produced. Trial questions are included and various versions of the test are prepared to avoid cheating. The test is printed in booklets that include test instructions and test items.
Equivalence of various test versions
The Center produces multiple versions of the same test. However, the Center has been cautious about discrepancies between various versions of the test in terms of difficulty , discrimination or content. An equivalence check is run during test construction based on scientific criteria to ensure test discrimination and differential capacity. Although it is more accurate to run equivalence test during construction stage, equivalence criterion is applied during and after the test.