Which factor can negatively impact the reliability of a test?

The factor that can negatively impact the reliability of a test is question ambiguity. Reliability refers to the consistency and stability of test scores over repeated administrations or different forms of the same test. When questions are ambiguous, test-takers may interpret them in various ways, leading to inconsistent responses that do not accurately reflect their knowledge or skills. This variation in interpretation can create measurement errors, resulting in reduced reliability.

For example, if a test question is not clear and could be understood in multiple ways, different respondents might answer it differently based on their own interpretations rather than their actual grasp of the subject being assessed. This inconsistency can obscure the true underlying abilities the test aims to measure, thus weakening the test's reliability.

In contrast, clear instructions, standardized administration, and consistent scoring procedures contribute positively to the reliability of a test by ensuring that all test-takers understand what is expected of them, that the test conditions are uniform for everyone, and that the scoring is applied uniformly, respectively.