Predictors and Socio-Demographic Disparities in STEM Degree Outcomes: A UK Longitudinal Study using Hierarchical Logistic Regression

TL;DR

This study uses hierarchical logistic regression on a nine-year UK university dataset to analyze socio-demographic predictors of first-class STEM degrees, revealing disparities based on ethnicity, course length, and gender, with implications for diversity and grading trends.

Contribution

It applies multivariate hierarchical modeling to UK STEM degree data, providing detailed insights into socio-demographic disparities and temporal trends in degree outcomes.

Findings

Black students have a 16% lower probability of first-class degrees compared to White students.

Students in 4-year programs are 24% more likely to achieve first-class degrees than those in 3-year programs.

Grade inflation was observed during the COVID-19 pandemic, with baseline odds rising from 2016 to 2021.

Abstract

Socio-demographic disparities in STEM degree outcomes impact the diversity of the UK's future workforce, particularly in fields essential for innovation and growth. Despite the importance of institution-level, longitudinal analyses in understanding degree awarding gaps, detailed multivariate and hierarchical analyses remain limited within the UK context. This study addresses this gap by using a multivariate binary logistic model with random intercepts for STEM subjects to analyse predictors of first-class degree outcomes using a nine-year dataset (2014 to 2022) from a research-intensive Russell Group university. We find that prior academic attainment, ethnicity, gender, socioeconomic status, disability, age, and course duration are significant predictors of achieving a first-class degree, with Average Marginal Effects calculated to provide insight into probability differences across these groups. Key findings reveal that Black students face a significantly lower likelihood of achieving first-class degrees compared to White students, with an average 16 percent lower probability, while students graduating from 4-year degree programmes have an average 24 percent higher probability of achieving a first-class degree relative to those on 3-year programmes. Although male students received a higher proportion of first-class degrees overall, our multivariate hierarchical model shows higher odds for female students, underscoring the importance of model choice when quantifying awarding gaps. Baseline odds for first-class outcomes rose considerably from 2016, peaking in 2021, indicating possible grade inflation during the COVID-19 pandemic. Interaction effects between socio-demographic variables and graduation year indicate stability in ethnicity, disability, and socioeconomic awarding gaps but reveal a declining advantage for female students over time.