Nearly one in three students doing a T-level in health and science drop out in their first year, according to a new report.
The Education Policy Institute (EPI) says T-level students overall are 20% less likely to complete their qualification than students on other types of courses.
Health students saw high levels of dropouts after botched exam papers in 2022, which saw the exam board responsible fined £300,000.
A Department for Education (DfE) spokesperson said the findings showed overall student retention rates were "improving as providers grow more familiar with delivering the courses".
T-levels are now in their fifth year, after first being rolled out in 2020.
They are two-year vocational courses taken after GCSEs, which focus on subjects like education, construction and IT, and include a work placement that makes up roughly 20% of the course.
Just over 16,000 students started a T-level in 2023. Although 2024 figures are not yet available, enrolment numbers have been rising each year.
But the rollout has drawn criticism from the regulator Ofsted, and the government's education select committee, with issues varying from the quality of teaching to the availability of work placements.
The latest EPI report also highlights a persistent issue with students dropping out of courses early.
The dropout rate of first-year health and science students was 31%, the report said. Only legal, finance and accounting courses had a higher rate, with 33%.
Aleasha Lancaster said three of her health T-level classmates dropped out after the exams fiasco in 2022.
Ofqual said it had had to take "unprecedented" action against the exam board, NCFE, to get 1,200 students' results recalculated, after it failed to develop "valid question papers".
Aleasha, 20, said it was a "big shock" when questions about "the acidity of volcanoes" came up in her science exam, rather than the health-based questions she had been preparing for.
The healthcare T-level is recognised by NHS Employers as one way young people can start their career in nursing, or other NHS roles.
Aleasha has gone on to study mental health nursing at university, but said she and her classmates often felt like "guinea pigs", having the course tested on them in real time.
"I think that because the lecturers didn't really know the course themselves, it was like the blind leading the blind," she said.
She said the course was sometimes disorganised, and lacked structure.
The EPI report also raised issues which many T-level students have found with using their qualification to get into university.
Nursing shortages
It comes after a warning from the Royal College of Nursing (RCN) last month, that the number of people studying to become nurses has "collapsed" in each region of England.
“Across the NHS alone there are tens of thousands of vacancies, and demand for services continues to rise," RCN's Prof Nicola Ranger said at the time.
"We desperately need more people to join the profession, but the reality is nursing numbers are going in the wrong direction."
UK-wide Ucas data from August found 23,800 students were accepted on to nursing courses for this academic year – 340 fewer than last year and 6,350 fewer than in 2021.
The EPI report found that nearly half of health and science T-level students who drop out early end up leaving education altogether.
It also criticised the T-level transition programme (TLTP), a foundation year of study to help students prepare for the T-level, with only 2% of health and science TLTP students progressing to the full course.
T-levels were launched by the former Conservative government, which planned to make them the main route into vocational education by defunding alternative courses, like BTecs, with overlapping subject areas.
Critics have warned that many students who might not be suited to T-levels could be left with fewer options for post-16 education if the alternatives are removed.
The new Labour government said it would continue with T-levels, but it is considering whether to continue defunding other courses.
The result of that review is expected before the end of the year.
A spokesperson from the DfE said: “We welcome these findings that show T-level students are more likely to go onto advanced apprenticeships and other higher levels of study than other vocational qualifications."