The careers guidance available to young people has become a “postcode lottery” that hinders social mobility, a leading charity has said.

The Sutton Trust says the National Careers Service - which offers telephone and web-based advice to schools - should also provide students with face-to-face advice from specialist careers advisers.

The call comes as a new report for the trust shows that where schools provide guidance of a high quality, there are improvements to GCSE results, attendance and access to leading universities.

The research, by academics at the University of Derby, compares schools that have received a “quality award” for their careers guidance with those that have not. After controlling for other factors, the study finds that at both GCSE and A-level, quality awards are associated with improved academic performance.

The report calls for the National Careers Service to be strengthened, giving schools access to professionally qualified advisers. The Department for Education should continue to improve the quality of the destination data that it collects on where students go to after their GCSEs and A-levels, it adds.

Yesterday, skills minister Nick Boles admitted that the careers guidance that had replaced the Connexions service was “patchy, not consistent or sufficiently open, porous, independent or impartial.”

He told the Association of Employment and Learning Providers autumn conference yesterday that he was “determined” to get it right, but that the process was “tricky”.

“I have not yet found a single place where everybody thinks careers advice and guidance is done well in a model we can replicate,” he added.

Conor Ryan, director of research at the Sutton Trust, said: “The overall decline in good guidance is harming social mobility. Having the right advice is key to young people making the right decisions. Those without good networks and family contacts lose out when careers guidance is poor.”

Professor Tristram Hooley, the report’s author, said the shake-up in careers guidance in schools had not been monitored “in any systematic way”.

He added: “Some schools have maintained high-quality provision and have given priority to preparing their students for the future, but many have not. We need a much stronger National Careers Service to support schools and colleges in delivering for young people.”

Related stories:

School careers advice is “nothing less than appalling”, college leader claims - 18 November 2013

Out-of-date careers advice stifling children’s job hopes, new report claims - 4 February 2014