School inspectors said the disparity was because councils are interpreting Scottish Government guidance on the issue in very different ways.
The report by Education Scotland concluded a majority of the best nurseries were those that employed teachers. The findings come six months after headteachers, teachers and parents attacked the Scottish Government's record on nursery education, arguing the service was being dismantled.
Key bodies and unions signed a joint statement warning of the impact of a decline in the number of qualified teachers in early years education – which has dropped by 12.6% since 2005.
In recent years, local authorities have replaced teachers with lower-paid child development officers – previously called nursery nurses – partly on cost grounds, but also because they work longer hours allowing nurseries to meet the demands of working parents. Political unrest over the issue has centred on the Scottish Government's policy of increasing pupil access to a qualified teacher, which critics argue is too vague and could even lead to teacher cuts.
In the wake of the report, the Education Institute of Scotland (EIS), the country's largest teaching union, called on the MSPs to introduce national, legally enforceable standards on access to a qualified teacher.
Larry Flanagan, general secretary of the EIS, said: "This report highlights that there is wide variation in practice regarding access to a teacher and concludes that occasional or ad-hoc support from a teacher is unlikely to make a difference – this is unacceptable in a country the size of Scotland."
However, Carol Ball, education spokeswoman for public service union Unison, said: "Child development officers plan and provide for the curriculum and educate children in nurseries to the same level as qualified teachers and, in some cases, our qualifications are more appropriate."
Minister for Children and Young People Aileen Campbell said: "Teachers are important to ensuring high quality early learning and childcare, particularly those with a specialist background in the early years.
"All early years managers are now required to hold or be working towards the BA Childhood Practice Award."