Having one or more university degrees no longer guarantees job security as the gig economy extends to highly skilled professions including law and big business.

Researchers from the University of Melbourne followed students who completed year 12 in 2006 and found those with Vocational Education Training (VET) qualifications were 2.5 times more likely than those with a masters degree or PhD to have a permanent job.

There are plenty of jobs around for self-employed plumber Josh Brown.

Researchers Jenny Chesters and Johanna Wyn said the findings, published in the latest issue of the Journal of Sociology, suggest "high levels of education provide little protection against insecure work". But those with degrees in insecure work were more likely to be working in fields directly related to their studies and finding greater fulfilment.

"Participants with VET qualifications were more likely than those with a postgraduate degree to be employed on a permanent contract; those with a VET qualification or bachelor degree were less likely than those with a postgraduate degree to have meaningful work as measured by having a job in field of study or having a high level of job satisfaction," the researchers said.