In late 2017, early 2018, there was significant media coverage about some Waitemata residents missing out on an invitation to participate in the Bowel Screening Pilot.

The Ministry takes full responsibility for what happened. Our approach has been one of open communication with those affected and with the public.

We hope these Q & As will go some way to clarifying the issue and give some reassurance about what we have done to improve our systems and processes to prevent these incidents recurring as we roll out the National Bowel Screening Programme (NBSP).

What happened?

Four separate incidents have been identified that occurred during the bowel screening pilot between 2012 and Jan 2018. They were caused in the main by issues with the IT system developed to run the Bowel Screening Pilot. The Ministry owns this technology.

Timeline of events

  • November 2017 – A review of pilot data during transfer to the NBSP Programme (NBSP) found that some people whose invitations were returned ‘not at this address’ were withdrawn from the Pilot. This meant that they didn’t receive further invitations even if an updated address became available. Around 2500 people were affected.

  • February 2018 – a second issue was discovered where people had notified the pilot programme of a change of address. These addresses were considered to be the most current so were 'locked' in the bowel screening register to prevent them being over-written by the daily automated NHI update. The consequence was that the locked addresses couldn't be altered if there was a subsequent address change. 333 people were affected.

  • April 2018 – A problem was identified relating to weekly data refreshes of the Bowel Screening Pilot (BSP) by the Ministry’s Data Warehouse. In some cases a person’s most recent address was not the one provided to the BSP. This was specifically a problem for people who had multiple NHIs. This issue affected 284 people.

  • April 2018  It was discovered that some people had been wrongly included in a so-called 'Do Not Load' list (of inactive NHI identities) when they should have been added to the bowel screening register. We estimate this issue affected 9,500 people.

How did this happen?

The issues arose as a result of shortcomings with the Bowel Screening Pilot IT system, combined with the enormous challenge of creating New Zealand’s first screening register using data from the National Health Index (NHI). 

What was the challenge with the NHI data?

At the time the pilot was being set up, the NHI indicated there were 240,000 eligible people 50 to 74 living in the Waitemata District Health Board area. By comparison, the census showed there were 160,000. Various IT tools and processes were used to resolve the data discrepancies and identify who was active and eligible but this continued to be a constant challenge.

How did the Ministry go about establishing a register of eligible people?

The criteria used to establish the pilot cohort was to invite people who were active in the health system. This was considered to be the most reliable formula for enrolment.

Because it is unusual for a person not to interact with some part of the health system for a long period, we suspect many people registered on the NHI have either moved overseas or were short-term visitors to our country.

How many were affected by the issues?

We estimate that up to 15,000 people may have missed out on being invited to participate in the pilot as a result of the combined issues.

How did these figures go from 2500 in February media reports to 15,000 in April?

This has been a process of discovery as part of the Ministry’s ongoing monitoring and quality review.

When the 9,500 missed invitations were discovered in April 2018, the Ministry took the unusual step of releasing this publicly before we informed those affected. We felt these numbers were significant and wanted to be upfront and transparent. By this stage there was significant public interest in the National Bowel Screening Programme and the Minister of Health had initiated a review after the earlier issues had been publicised.

What has been done to make amends to those impacted?

The Ministry regards these incidents as serious and has taken the view that those who missed out on screening invitations were adversely affected. Letters of apology have, or are, being sent as well as a screening invitation and test kit.

In every case we cross-check with the cancer registry to establish whether any of those affected have gone on to develop bowel cancer. If they have, a clinical review is carried out to establish the timing of the diagnosis to determine whether screening could potentially have made a difference to the outcome. In such cases we make contact with the individual’s GP and offer to personally meet the person to explain what happened and to apologise.

This is an ongoing process and it will take time to work through as those affected are invited for screening.

What’s been done to ensure this won’t happen with the National Bowel Screening Programme?

Since the identification of the first issue in November 2017 the NSU has continued to correct anomalies and put systems and processes in place that will provide assurance around the invitation process. This includes:

  • a senior analyst continuously reviewing all data anomalies across the screening pathway for all participants

  • the development of a tool to measure invitation cohorts for each DHB against census data to identify significant differences

  • improving the quality of NHI data. The quality of data on the NHI has improved significantly since it was used to create the Waitemata pilot cohort

  • the expansion of Fail Safe reports to cover ‘known issues’ to prevent any chance of a reoccurrence.