The Ministry of Health has apologised after mistakenly inviting more than 1000 people diagnosed with bowel cancer to get a bowel screening.
The National Bowel Screening Programme is intended to find bowel cancer at an early stage, for better treatment outcomes.
But due to a computer fault, people who had already been diagnosed with the cancer were mistakenly invited to get a screening.
There was supposed to be automatic filtering when the letters were generated, Director-General of Health Dr Ashley Bloomfield says.
He says 1262 people were mistakenly sent the letters in the Tairawhiti, Canterbury and Southern Canterbury DHB areas after the computer fault.
Of those, more than 200 people have already contacted the Ministry of Health in distress.
"We know that coping with cancer is uncertain and stressful and we are sorry we have added to that distress through this unfortunate error," Bloomfield says.
Chief Medical Officer Andrew Simpson says they've apologised to the people who have got in touch already and will be providing a written apology to everyone who wrongly received the letters.
"The names of patients on the registry, who had previously been diagnosed with bowel cancer, should have been taken out of the list of people invited for screening but that didn’t happen," he says.
The Ministry of Health is working on a permanent fix to stop letters being sent out if the filtering fails again, it says.
Anyone who is concerned is asked to contact the National Bowel Screening Programme on 0800 924 432.