Students from deprived areas who are accepted into university with lower grades under a pioneering access scheme perform just as well as their middle-class peers with better school qualifications, new research shows.

Pupils from disadvantaged backgrounds who go to university are often at greater risk of dropping out because they are unfamiliar with the environment and do not always have parental support.

It has been argued universities are "dumbing down" if they admit students with lower grades to widen access. But research by Glasgow University into 1000 students who secured a place at the institution after attending its ground-breaking Top-Up programme in the last decade appears to show the reverse is true.

The study shows students who entered through Top-Up have higher progression rates into second year than students entering from state schools in more affluent areas with a culture of sending a higher number of students to university.

The research also suggests the students are doing well in their studies – despite being allowed to enter with lower grades – because they have to meet the same academic standards required by their peers to be admitted to the second year.

Since 2001, 17.4% of first-year students who went to university through Top-Up dropped out of their courses, compared to 18.1% of students from schools in more affluent areas.

Figures are also improving, with just 12.4% of Top-Up pupils dropping out in 2010 compared to a rate for more advantaged pupils of 13.5% for the same year.

University principal, Professor Anton Muscatelli, welcomed the figures and said the institution was determined to do more. "We are looking to identify students as early as possible in secondary schools and help them to raise pupils' ambitions and do more than just intervening in the final years, when it may be too late," he said.

Mr Muscatelli dismissed suggestions that students from deprived backgrounds with lower grades were less capable than those from middle-class homes or who attended private school.

"In many respects the reverse is the case because we find these students are more motivated than students who haven't had to fight to get into university and we find they are just as able, if not more able," he said.

However, Liz Smith, education spokeswoman for the Scottish Conservative Party, said all students should be offered the opportunity of taking part.

She said: "There is a need to help all students from whatever background to deal with university life as well as the academic challenge.

"That is why I am very persuaded of the need to focus the widening access debate on all our schools."

Under the Top-Up initiative, bright pupils from schools in deprived areas across the west of Scotland join a nine-week access scheme both to familiarise them with higher education and assess their potential.

Those who pass are admitted onto courses even if they drop a grade in two of their chosen subjects for entry to degrees in the Arts, Social Sciences, Sciences and Engineering.

Candidates who apply to Law, Business, Education or Nursing are allowed to drop a grade in one subject.

Dr Neil Croll of the university's access widening unit said the scheme gave a level playing field to all students for the first time.

"Entrants through Top-Up are regarded as having equivalent entry conditions as those entering without the programme because of the rigorous nature of the project," he said.

Robin Parker, president of NUS Scotland, which represents students, said: "While universities can't do it all to achieve fair access, work like Glasgow's University's Top-Up scheme can get great results, levelling the playing field."