Scotland’s school subject squeeze is hitting pupils in disadvantaged areas the hardest, new research shows.

The findings in a report by academics from Stirling University comes after Education Secretary John Swinney told The Herald there was more choice than ever before in schools.

The research comes after concerns over a reduction in the number of National 5 qualifications on offer in many schools.

Figures from the Reform Scotland think tank show a majority of schools now only offer six subjects in the fourth year of secondary school because of timetabling difficulties following the introduction of a broader curriculum.

READ MORE: Why greater choice also means a subject squeeze

Research by Stirling University academics Dr Marina Shapira and Professor Mark Priestley found the squeeze was concentrated in schools serving more disadvantaged communities.

The report, which looks at exam data between 2011 and 2017, concluded that the senior phase of the school curriculum had become “narrower” since 2013 when new qualifications were introduced.

It said: “The size of this reduction has not been uniform, but has varied between schools of different characteristics, between areas with different levels of deprivation and between local authorities across Scotland.

“The findings show that the socio-economic status composition of school intake has a strong association with the number and configuration of subject entries.

“A larger reduction in the number of subject entries for National 5 level qualifications took place in schools in more deprived areas, as well as in schools with a larger number of students from disadvantaged socio-economic backgrounds.”

READ MORE: John Swinney: I don't see a narrowing of choice

The report also noted a more pronounced decline in subject choice in schools where the proportion of pupils with additional learning support needs was higher, and in schools with poorer staff-student ratios.

Researchers added: “We also found the number of subject entries was smaller in schools where the overall number of subjects offered for National 5 level qualifications was smaller.

“Furthermore, we found that schools in areas of higher deprivation and schools with larger numbers of pupils from disadvantaged backgrounds had smaller proportions of young people enrolled in sciences and modern languages, and a larger proportion of pupils enrolled in vocational subjects.”

In 2015, Cristina Iannelli, Professor of Education at Edinburgh University, said education systems such as Scotland’s with flexibility over curriculum choice allowed social inequalities to emerge because “more socially advantaged parents” were better placed to ensure their children made the best decisions over what subjects to take.

In an interview with The Herald on Tuesday, Mr Swinney said judging Scotland’s education system by the number of subjects pupils sit in S4 was a mistake.

He said: “It is an important question being posed about whether there is narrowing as a consequence of the subject choices being made and the nature of the curriculum, but we have to have a much broader look at what the curriculum is offering.

“I understand the view, but I disagree with it because I don’t think it is the critical test of the value of our education system. It is a mistake to look at one particular moment in the senior phase because we have to look at it in totality.

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“There are various curriculum models designed around the country which in my view deliver breadth for young people, but perhaps not in the fashion that breadth was delivered when I was going through the education system in the 1970s and early 1980s.”

Mr Swinney said he had no issue with the current variety in S4, with a majority of schools offering six subjects, but some allowing pupils to sit eight or and nine.

“What matters to me is that schools should be satisfied that the curriculum model they take forward has been the subject of active dialogue with their pupils and communities and that they are satisfying themselves as professional educators that the model they deploy fulfils what we expect of our schools,” he said.

“That will lead to a variety of models and that doesn’t trouble me one bit because I want to have an empowered school system and if we have an empowered system I accept that will lead to variety.”

The latest report from Stirling University found the average number of National 5 subjects per student in S4 decreased between 2011 and 2014 from an average 7.3 to 5.5. There was a further drop from 5.5 to an average 5.13 for years 2015-2017.