Testfairness

Testfairness, or test fairness, denotes the fairness of tests and the validity of decisions based on test scores across diverse populations. It aims to ensure that scores measure the intended construct and are interpreted equivalently, regardless of characteristics such as race, gender, language, or disability, while providing equal access to participate and accommodations as needed.

Definitions and concepts: In psychometrics and policy contexts, several fairness criteria are used. Demographic parity seeks equal pass rates across groups; equalized odds requires equal false positive and false negative rates; predictive parity asks for equal positive predictive value. Individual fairness requires similarly situated individuals to receive similar scores. Differential item functioning (DIF) analyses detect items that function differently across groups, while measurement invariance tests check whether a test measures the same construct in the same way for different groups.

Sources of unfairness: Construct bias, item content that reflects only one culture, language barriers, translation issues, sampling bias, test administration conditions, and unequal access to accommodations can all distort results. In some settings, systemic factors influence performance independently of ability.

Approaches to promote fairness: Use diverse development and validation samples; conduct DIF and invariance analyses; design tests with accessible formats; provide appropriate accommodations; report disaggregated results; and conduct ongoing bias and impact monitoring throughout the test life cycle.

Trade-offs and regulation: Striving for fairness can interact with overall validity and reliability, and acknowledging trade-offs among fairness definitions is common. Ethical and legal obligations require transparency, nondiscrimination, and continuous improvement. Fairness auditing and impact studies help organizations detect and address disparities.