The evaluation team is expected to confirm the education department’s conclusion that Douglas Duff, Hailesland’s headteacher, failed to comply with council guidelines and procedures in dealing with allegations of bullying and other incidents.

The authority announced at the weekend that Mr Duff, aged 59, who has been head of the school in the Wester Hailes area of the city for more than 23 years, is taking early retirement on medical grounds. Ronnie Summers, headteacher of the neighbouring Sighthill primary, is taking charge for the time being.

Elizabeth Maginnis, Edinburgh’s education convener, said in a statement: “The headteacher has, in our view, probably not been applying some of the council policies around the issues of child safety and anti-bullying as effectively as we might have expected. In the course of examining the various allegations from parents, it became clear that his own ill health has been contributing to some of the difficulties he has been in. So he has applied for early retirement and we have accepted that.”

Four families withdrew children following a playground incident in which a girl aged 11 was allegedly sexually assaulted by a boy of the same age. The education department said this week that only one of the parents was refusing to send her daughter back to Hailesland. A diary detailing bullying said to have been suffered by the girl, aged 10, was published in a local newspaper.

The council’s investigations are believed to have uncovered a recent history of conflict between the parents and the school’s senior management. The absence of a school board and parent-teacher association meant there was no forum for conflicts to be resolved or brought to the attention of the education department.

Hailesland hit the headlines last month when a three-year-old from the nursery left the school unnoticed and started to walk home alone. The first the council knew of the incident was when it was reported in the press.