A review of NHS whistleblowing by Sir Robert Francis QC will be delayed until next year, HSJ can reveal.

The Freedom to Speak Up review was due to be published this month but has been delayed due to the high number of contributions and evidence it has received.

Sir Robert, who chaired the public inquiry into care failures at Mid Staffordshire Foundation Trust, was asked to carry out a review of how the NHS treats whistleblowers by health secretary Jeremy Hunt, following concerns of a culture of cover up and victimisation of those who raised concerns.

Since it was launched in August the review has received more than 600 written contributions and 17,500 responses to an online survey.

A spokesman for the review said: “In view of the very high volume of contributions to the review, it has been agreed Sir Robert Francis will publish his final report early in the new year.”

In an earlier interview with HSJ Sir Robert accepted the timeline for the review was “tough” but added it was necessary for his work to be useful before the general election in May 2015.

Sir Robert has appointed a series of advisers to support his work and has hosted a string of seminars with invited guests to explore the issues and come up with solutions.

The review has also commissioned two separate pieces of research by Middlesex and Greenwich universities into whistleblowing in the NHS and to gather the views of NHS staff.