The numbers of students starting university courses after studying Btecs is rising - but they are less likely to graduate with a top degree than their peers who took A-levels, a study has found.
It argues that there are still misconceptions about the abilities and qualifications of those who choose to study alternatives to A-levels.
The University of Sheffield , which carried out the research, said it was 'crucial' that these misconceptions are challenged to ensure that higher education is open to all.
The findings come as a major independent review of post-18 education, including vocational and technical courses, gets under way.
The study saw Sheffield University work with local colleges over an 18-month period to look at the transition of students who had studied courses other than A-levels, to studying at the institution.
It found that the numbers of students at the university who had studied Btecs - a leading vocational qualification - alone had doubled from 202 in 2011 to 412 in 2017.
During that period, the numbers with A-levels only had remained static, from 13,437 in 2011, to 13,443 in 2017, while the numbers that held both A-level and Btec qualifications had soared from just 36 to 377.
"The numbers of students holding a Btec has increased over time as a percentage share of university applications," the study says, adding that apprenticeships and the Government's new T-levels (technical qualifications) "are likely to increase the trend towards a greater mix of pre-entry level qualifications, other than A-levels".
The figures also show that those with Btecs, or a combination of qualifications, are less likely to leave university with a first or 2:1 than those who just studied A-levels.
Overall, just over 80 per cent of A-level only students gained a good degree in 2011, compared to just under 80 per cent for those with Btecs and A-levels and around 50 per cent of those with Btecs alone.
By 2016, around 90 per cent of A-level students were getting a first or 2:1, compared to around 80 per cent of those who both types of qualifications, and just over 60 per cent for those with Btecs only.
"Overall, the percentage of students who obtained a good degree during 2011-2016 is consistently higher for students who entered the university with A-levels only, but it is not clear whether this can best be explained by differing ability or by the fact students with equivalent qualifications are less understood or less recognised as a minority, or other reasons," the study says.
It also concludes that views of students and staff involved in the study show that it is important that there is a better understanding of Btecs and degree content.
"This can help to challenge possible misconceptions, biased perceptions and 'snobbery' by supporting better informed views," it says.
It also says: "Without evidence there is a danger the perception that vocational qualifications do not prepare students well for higher education causes direct discrimination against those holding equivalent qualifications to A-levels and indirect discrimination against those from lower socio-economic backgrounds and black and minority ethnic backgrounds.
"There is also a danger that those students holding equivalent qualifications and with the potential to succeed in a selective university are denied the opportunity to do so."
Sheffield, a leading institution that typically asks for high entry grades, said it was expected that the results of the project are reflective of issues faced around the country by students with different qualifications.
The study calls for universities, schools and college to work together to explain Btecs and bust myths, which would help admissions officers to make decisions about potential students' qualifications and their chosen degree course.
Professor Wyn Morgan, Sheffield's vice-president for education, said: "Challenging misconceptions about students who come to university via equivalent Btec qualifications compared to those on the traditional academic route of A-level is crucial, as higher education should be open to all those with talent and ability.
"The findings have helped us develop greater awareness and understanding of equivalent qualifications, as well as provided universities with recommendations to further develop their own teaching and support in order to continue to offer students the best possible experience at university."