Misconceptions about Group Differences in Average Test Scores
Posted: November 22, 2019
The recent request to the Regents of the University of California to stop using college admissions test scores pointed out the troubling reality that there are large score differences across racial/ethnic groups on college admissions tests. However, the letter reinforced two misconceptions about tests that need to be corrected. First, the letter claimed that differences across racial/ethnic groups in test performance signify test bias. Second, the letter claimed that the typical finding that students from high-income families obtain higher test scores, on average, than students from low-income families constitutes proof of test bias. These erroneous claims confuse correlation with causality. Differences in socioeconomic status and quality of education exist across racial/ethnic groups in this country. Criticizing test results for reflecting these inequities is like blaming a thermometer for global warming. For this reason, the Standards for Educational and Psychological Testing (American Educational Research Association, American Psychological Association, and National Council on Measurement in Education, 2014) explicitly point out that test fairness does not require equality of outcomes. As the Standards state “…group differences in testing outcomes should trigger heightened scrutiny for possible sources of test bias … However, group differences in outcomes do not in themselves indicate that a testing application is biased or unfair” (p. 54). Some examples of factors that may contribute to average score differences across racial/ethnic groups are disparities in school and community resources, teacher quality, course offerings, and access to cultural activities. The National Council on Measurement in Education is troubled by these inequities and would like to see educational assessments be part of the solution in resolving them. However, we note the disparities in test performance are caused by disparities in educational opportunities, and that group differences in college admissions tests do not equate to test bias. Rather than limiting the types of information college admissions officers can use, we encourage proper use and interpretation of all data associated with college readiness, and we acknowledge the importance of the information provided by college admissions test scores.
To learn more about how the National Council on Measurement in Education works to improve equity issues in education, including travel scholarships for minority graduate students in educational measurement, visit www.NCME.org.