Pre-school education is good for everyone and especially for children who show early signs of developing special educational needs. The long-term study of 3,000 children in six local authorities south of the border is heartening evidence that Labour’s pre-school and early intervention policies are heading in the right direction. Ministers will be comforted by the hard indicators of success in educational and social terms after pumping in millions over the past six years. Pre-school is rightly assuming the importance it should and the findings apply equally to Scotland where there is a research gap.

But early triumphs merely throw up other questions and point to the inadequacy of what we have compared with other European systems. Can we, for example, channel more resources into pre-school and head off difficulties before teachers face more deep-seated problems in class? Can we offer more than daily part-time sessions in nursery? Parents still complain of patchy and costly provision outside of nursery which prevents them from working. Can we further improve the quality of experience?

On a professional level, the Oxford and London university findings will bring equal comfort to the teaching lobby which has been under severe pressure to concede ground in nurseries. The teachers’ position of lead professional is under threat and many local authorities argue that others can match their skills and knowledge - and more cheaply.

The latest research will fuel the debate on professional boundaries. At its core is the level of staff qualification and training. The more highly trained staff become, the higher return for children. At present, these happen largely to be teachers. But that may change as ministers north of the border relax the regulations on having a trained teacher in a nursery or leading a nursery.

What matters, according to researchers, is the level of understanding and knowledge teachers have about how children learn - what is generally called effective pedagogy. Teacher interactions with children are better and more open-ended. The challenge for councils which want others more closely involved is to bring them up to teachers’ levels of training and experience. At the same time, will teachers want to work in pre-school settings when their bosses are making it quite clear they are no longer top dog?