IT IS "impossible to determine" whether more could have been done to save a 33-year-old woman who called the NHS non-emergency number but died before receiving a response from a doctor, an investigation has found.
However, neither the report or its recommendations will be published.
The woman, who has not been named, called 111 with a unidentified health complaint on December 22 last year only for her condition to "rapidly deteriorate" before a GP returned her call within two hours.
When paramedics arrived at her Croydon home they were unable to resuscitate her.
An investigation into her dath, which concluded this week, was unable to determine whether a faster response would have saved her life, health bosses said.
They have decided the report will not be published because it would "break patient confidentiality".
Harmoni, the private firm contracted to operate 111 in south west London by Croydon Clinical Commissioning Group (CCG), conducted the investigation. The company has since been rebranded as Care UK.
Spokesperson Sheila Roberts said: "We would like to offer our sincere sympathy to the patient's family and friends. Care UK and Croydon CCG has taken this matter very seriously.
"Although the rapid deterioration of the patient in this case means that we will never really know if we could have done anything different to change the final course of events, we want to make sure we do all we can to learn from this investigation and make changes that will strengthen the service."
Care UK said the report had been delayed to include a coroner's findings. It is understood the coroner has decided not to hold an inquest into the woman's death.
Ms Roberts added that details of the report could not be made public but said the family had been involved in the process.
Dr Agatha Nortley-Meshe, clinical lead of NHS 111 at Croydon CCG, said: "Our thoughts and sympathies are very much with the patients family at this difficult time.
"As the commissioner for this service in Croydon, it is our responsibility to oversee the investigation and ensure any recommendations are properly.
"The report concludes that in the light of the patient's rapid deterioration, it is impossible to determine whether there was anything the 111 service could have done that would have made a difference.
"However, Croydon CCG takes its responsibilities very seriously so we will be working closely with the provider to make sure NHS 111 learns all it can from this incident and continues to offer the best possible service for the people of Croydon."
A separate investigation has found Croydon CCG included "inappropriate" information about the woman's death in the January board paper it was initially mentioned in, even though it included no name, age or address, and very little about what happened.
