Up to 15,000 people in Auckland may have missed out on invitations for a free bowel screening, The Ministry of Health has discovered.
The issue was caused by an IT problem and human error.
The invitation was part of the Ministry's bowel screening pilot programme which invited almost 200,000 Waitemata residents between 2011 and 2017 for a free screening.
Around 117,000 were screened successfully but up to 15,000 people missed out.
National Screening Unit clinical director Dr Jane O'Hallahan said the Ministry took full responsibility for the oversights and would continue to contact those affected to apologise and invite them for screening over the coming months.