The health service ombudsman is seeking to broaden the scope of her office’s investigations into complaints about health treatment by probing systemic failings at NHS bodies, HSJ has been told.

In an exclusive interview, the ombudsman, Dame Julie Mellor, also revealed an external review is to take place into how the regulator handles cases of potentially avoidable deaths.

The proposals constitute a response to criticism of the performance and powers of the ombudsman, whose NHS role is to take up complaints unsatisfactorily dealt with by the organisations themselves. The ombudsman’s office has been under fire for failing to investigate the circumstances surrounding some deaths.

Dame Julie, who started work in the role in January after Ann Abraham stepped down, also revealed to HSJ she planned to improve her office’s ability to share information with coroners and other regulatory bodies such as the Care Quality Commission.

And she plans to set up a telephone service offering advice to people with complaints about NHS treatment about where they should go for support.

Dame Julie said parliamentary approval would be required to “expand the scope” of the body’s investigations into “wider systemic issues”. At present the ombudsman can only investigate matters the complainant has directly mentioned.

“Where there is service failure as serious as an avoidable death, behind that is probably some poor supervision or some bad systems or procedures relating to how some service is operating,” she said.

“That’s why I want to widen the scope [of investigations] so I can feed those lessons back into the system.” This information could be shared with sector regulators.

It is hoped draft legislation prepared as part of Cabinet Office minister Francis Maude’s open government reform could offer an opportunity to make the change.

Dame Julie told HSJ the external review would be led by Baroness Rennie Fritchie, chair of the 2gether Foundation Trust in Gloucestershire. The review’s remit would be to improve the service offered by the ombudsman to complainants and provide better information for sector and professional regulators.

She said the plans for the phone advice hub were expected to take two years to develop and were modelled on a system used by the financial services ombudsman. She said it could also act as an “early warning system”.

“If there is concern about a particular unit at a hospital and we are getting a cluster of calls to a complaints hub about it, that’s data that could prompt a further look by the CQC,” she said.

The ombudsman’s office has been criticised by complainant James Titcombe for its failure to investigate possible maladministration by NHS North West, in its role as a local supervisory authority for midwives. Mr Titcombe claims this was a factor in the poor care of his son Joshua at University Hospitals of Morecambe Bay Foundation Trust prior to his death in 2008.

An internal review by the ombudsman’s office said the regulator’s decision not to fully investigate the case did not “stand up to scrutiny”.

Dame Julie declined to discuss individual cases but said the Titcombe family’s complaint was “the kind of case” covered by the review.