GPA Versus Exam Scores: What's Better in Predicting College Success?

• By Dian Schaffhauser
• 03/09/17

High school grade point average serves as a better predictor of college success than standardized exam scores among students heading directly into higher ed from high school. But among those who delay their college entry, the same isn't necessarily the case; it depends on the type of test and the subject under consideration.

These findings came out of research undertaken by Education Northwest, one of 10 regional educational laboratories that do applied research to improve academic outcomes for students. The project was a follow-on to research undertaken last year by the same organization to examine developmental education placement rates and how well high school grade point average and exam performance predicted performance in college-level courses among first-time students entering two- and four-year programs at the University of Alaska system.

This time around, researchers wanted to explore subgroups of students — specifically those who come from urban areas versus rural areas of Alaska and those who headed right to college compared to those who waited a while. The data consisted of student-level administrative information on 17,940 first-time U Alaska students enrolled from fall 2008 to spring 2012.

The results could have implications for "K-12 education stakeholders" who want to develop "college-readiness indicator systems" for their states or districts, according to the authors of the recent study.

The project asked two questions:

• How well does high school GPA predict performance in college-level English and math courses among recent high school graduates from urban and rural areas of Alaska?
• How well does GPA predict performance in college-level English and math courses among students who entered the university within a year of high school graduation and those who delayed their college entry by at least a year?

In answer to the first question, GPA was a better predictor of college performance than scores on the SAT, ACT or ACCUPLACER tests. In the parlance of the researchers, "Regardless of where in Alaska students came from, high school [GPA] explained more of the variance in college performance than did standardized exam scores."

Consistent with research at California community colleges published in 2014, high school GPA also explained more of the variance in college-level English grades than in college-level math grades.

In answer to the second question, among students who delayed college entry, GPA didn't consistently turn out to be more predictive than standardized exam scores. It depended on the subject and exam. Compared to SAT and ACT scores, GPA was a better predictor for success with college English. But compared to the ACCUPLACER scores, the percentage of the variance in college-level English grades explained by GPA was only one point greater. In math, the percentage of the variance in college-level math grades was just a point higher than the percentage explained by SAT scores. GPA was less predictive of college-level math grades than were ACT and ACCUPLACER scores.

What this all suggests, said the researchers, was that exam scores are just one ingredient to be used in student placement decisions. GPA "may be a useful additional tool for making more holistic course placement decisions, because it contains unique and valid information, not captured by standardized exam scores, about students' likelihood of succeeding in college courses."

The report, "How well does high school grade point average predict college performance by student urbanicity and timing of college entry?" is freely available on the Institute of Education Sciences website here.