The hospital failings that gave nurse Colin Norris his chance to kill four times

The independent investigation made a total of 32 recommendations for changes in patient safety measures, staff recruitment, death certification and medicines management in the wake of the crimes committed by staff nurse Colin Norris in 2002.

The report emphasises that responsibility for the intentional harming of the patients rests firmly with Norris and it remains impossible to create a totally safe environment to eradicate the risks posed by an individual with criminal intent.

But it says a combination of organisational and cultural factors at hospitals in Leeds gave him the opportunity to commit his crimes.

It found systems at the hospital to monitor the supply and administration of drugs in 2002 were not sufficient to identify and prevent malpractice and safety checks were not embedded in the city's hospitals.

The hospital mounted internal investigations into the activities of Norris and a second nurse who was found to be stealing painkilling opiates, making 147 recommendations for change.

But the report said significant changes needed to address deep-rooted issues were "lost in a mass of small changes" and the action plan lacked direction and focus.

By 2008 there were still actions outstanding and there was a lack of evidence others had been fully implemented. Recording "adverse incidents" was significantly behind in many departments – in some cases by as much as 18 months.

Some junior doctors told the inquiry they were not even aware of how to report safety incidents.

The team found poor record keeping at the hospitals. Medical records were still illegible and lacked vital information, and the team highlighted problems with death certification.

This was raised by the inquiry into serial killer Harold Shipman and its chairman Dame Janet Smith expressed concerns to the team about the similarities between the offences by Norris and Shipman.

All four of Norris's victims died of hypoglycaemia but this was not even recorded on the death certificates of the first three victims, which "should have been identified as suspicious deaths", said the report.

It added: "The independent inquiry team believes that if unexpected/unexplained deaths and incidence of hypoglycaemia had been assessed and investigated and if death certificates had been accurately completed, Colin Norris's actions might have been identified earlier."

The report found management of medicines had improved but there had been little action to use the latest technology to reduce risks to patients.

There was also criticism that problems during Norris's training in Scotland were not picked up as his references failed to reveal his poor sickness record and his attitude towards older people which the inquiry team found questioned his suitability to be a nurse.

Hospital chiefs said yesterday work had been carried out to make sure drug prescribing was safe and administered correctly.

Improvements had also been made to death certification to ensure they were accurate and comprehensive when they were being completed.

Audits were also being carried out of more than 3,000 deaths at the city's hospitals each year including reviews of case records and outcomes from treatments.

TIMELINE OF MURDER OVERDOSE

October 2001: Nurse Colin Norris begins work on ward 36 at Leeds General Infirmary.

May 17 2002: Patient Vera Wilby, 90, collapses after being given a huge overdose of insulin.

June 25 2002: Doris Ludlam, 80, is attacked and dies two days later.

July 21 2002: A third patient Bridget Bourke, 88, collapses and dies the next day.

September 2002: Norris transferred to ward 23 at St James's Hospital.

October 20 2002: Patient Irene Crookes dies on her 79th birthday from an insulin overdose.

November 20 2002: Norris, working an extra shift at the infirmary, attacks Ethel Hall, 86.

December 6 2002: Police are called in after tests reveal she has been given a massive overdose of insulin.

December 11 2002: Ethel Hall dies. The same day Norris is arrested and questioned.

October 12 2005: Norris is charged with murdering four elderly patients and attempting to murder another.

March 4 2008: He is given five concurrent life sentences and told he must serve a minimum of 30 years.

April 20 2009: Norris is struck off the nursing register.

December 21 2009: An appeal against his conviction fails.

December 30 2009: A NHS compensation pay-out of 47,500 is awarded to Doris Ludlam's family.

January 26 2010: An official report makes 32 recommendations for change.