An inquiry into the death of a child in Birmingham is among 23 Serious Case Reviews judged to be inadequate by watchdog Ofsted.
The review, which looks at the actions of social workers and other agencies, was conducted earlier this year.
But the identity of the child is not being revealed by Ofsted.
At least 20 children have died of abuse or neglect in Birmingham in the past six years – with 17 known to social workers.
Birmingham City Council has initiated 22 Serious Case Reviews into child deaths or serious injuries since January 2004. They were conducted by the city’s Safeguarding Children Board.
Last year the board was told by Ofsted to undertake some of the case reviews again because the reports were not good enough.
Across the country one in six Serious Case Reviews this year were found to be inadequate by Ofsted.
Of the four looked at in Birmingham, three were rated as adequate. None were deemed good.
The report also found that many reviews are not being completed quickly enough.
While 60 were completed in the set six-month timescale, 60 took up to 12 months, 19 took between one and two years and eight took over two years.
The study found that many of the cases reviewed showed there are still persistent shortcomings in the protection of vulnerable children.
In many cases, the workers involved failed to follow good practice or guidelines that had been made available.
Agencies such as health, social services and the police failed to work together on some occasions, while in others workers accepted and failed to challenge the information given to them by parents and carers.
