Are Weighted or Unweighted High School Grade Point Averages Better Indicators of College Success?

Abstract

Multiple studies have shown the strong predictive power of high school grade point average (HSGPA) in forecasting future academic performance outcomes. However, the methods for calculating HSGPAs vary among schools, with some employing weighted methods in their calculations and others using unweighted scales. Due to these inconsistencies, it is often difficult to compare HSGPAs across high schools. This study involved the coding of 551 high school transcripts of pre-med college students in Texas. Unweighted HSGPAs were then calculated for each of these students on a standard 4.0 scale. Three multiple regression models were then created for the students with complete data (n = 520), and it was found that unweighted HSGPAs are statistically significant predictors of college GPA (CGPA). Additionally, in the presence of certain conditions, specific demographic variables, as well as SAT scores, were also indicative of measures of academic success, as defined in this study as the student’s CGPA, whether the student took the Medical College Admissions Test (MCAT), and the score the student achieved on the MCAT. In light of our findings, we strongly suggest discontinuing the use of the current system of weighted HSGPAs as predictive measures for gauging the likelihood of future academic success.