Within the last decade or so there has been a revolution in the way that we think about evidence. This has been especially apparent in the context of research into education. Since their establishment in 2011, the Education Endowment Foundation has conducted more than 200 Randomised Controlled Trials (RCT), across thousands of settings and with millions of young people. Elsewhere, the Department for Education has invested millions in a research centre on adult skills and knowledge and the Office for Students (OfS) has funded the Centre for Transforming Access and Student Outcomes in Higher Education (TASO), where two of us are affiliated.

There are some common focus points that all of these initiatives share: firstly, a focus on improving access and attainment in education at various levels and secondly, a focus on ‘What Works’ – essentially the examination of whether an intervention, such as a programme to improve GCSE grades, actually achieves its desired intention. To answer these questions, experiments – such as the above-mentioned RCTs – are often used as this method aims to provide robust evidence of the impacts of an intervention. Collecting robust evidence is important as it lets us meaningfully differentiate between the good, well-intentioned ideas that are nonetheless ineffective, and those that actually make a positive difference to people’s lives. However, it is important to note that these methods only provide a partial view, especially for those of us interested in equality.

A recently published paper puts this into sharp relief. The study, which is based on US data, looks at returns to higher education, and how this differs between male and female students.

The picture presented from this study is mixed, and this is what makes it interesting. If we take a look at earnings, a female student might get a wage premium of 15% from studying psychology and social work, while a male student gets no wage premium at all. In nursing, female students get a 27% premium, but this is dwarfed by a nearly 60% premium achieved by male students. The differences are not only a matter of degree, but also one of direction – a master’s in humanities gives female students a 3.4% earnings premium, but costs male students more than 20% of their income. Differences such as these can be observed throughout the paper.

The findings collated from this study turn some of our misjudged preconceptions about degrees on its head. Fine arts – often decried as a degree that costs its students’ income – only holds a negative effect for male students whereas female students see marginal increases in their income. Whilst this is data from the United States, the research could be replicated in the UK.

In further exploration of equality gaps in employment and employability, TASO have recently published a report on ‘What Works’ to reduce these gaps using Longitudinal Education Outcomes (LEO) data from the Department for Education to better understand the descriptive differences in employment outcomes and earnings between groups of students.

The descriptive analysis found that when compared to other forms of equality gaps, the trajectory of the gender earnings gap is particularly striking. For example, in the year following graduation, male graduates earn 8% more than female graduates, but in the following nine years this grows to a gap of 32%. This implies that the equality gap, whilst present initially, readily widens over time furthering that disparity in earnings between males and females following graduation.

The TASO report also found that subject choice contributes to the initial differences in earnings between male and female graduates. However, as graduates age, a larger proportion of this gap is explained by other factors such as differences in parenting responsibilities, hours worked, the propensity to ask for pay rises or apply for promotions and labour market discrimination. Interestingly, in a report published last year, the Institute for Fiscal Studies (IFS) found that by age 30, subject choice explains only a fifth of the total gender pay gap. Hence, these additional factors are important to recognise when examining the years following a student’s graduation.

In the UK, we’ve seen the proportion of individuals attending Higher Education and pursuing post-graduate degrees increase over recent decades. This is particularly true of women, however, we still observe notable gender differences in course type. For example, the University of Oxford’s most recent admissions report shows that female students make up just 15% of the total students studying mathematics and computer science while Biology is 63% female and English 76%. We lack evidence about the impact of these trends on returns for both women and men.

It is important to acknowledge the wider context to this area of work. The Global Institute for Women’s Leadership (GIWL), directed by Rosie, aims to provide evidence about how best to improve outcomes for women and girls around the world. Much of the work of the ‘What Works’ network, while incredibly valuable, can sometimes flatten our understanding of student experiences in its pursuit of average effects. What the research discussed in this blog shows is that we can’t rely on a rising tide to lift all boats. Instead, we should make it a priority to design studies, as well as re-evaluate historic trials, to look at different effects for people of different genders. If we do not do this, there’s a danger that our best efforts are actually making things worse for women and girls.