Dear Ed,

Wales Cancer Services Statistics designation

I am writing to ask you to consider designating the Welsh cancer services statistics as National Statistics.

Our cancer services statistics were established in their current form in June 2019. The new series ran in parallel with an existing series until November 2020, when the old method was stopped. The previous series was collected on the basis of urgent and non-urgent cancer pathways, while the new series reflected the single Suspected Cancer Pathway (SCP), a Welsh Government target for diagnosing cancer and starting treatment more quickly. The new method replicated the scope of the previous method, but is based on patient level data rather than an aggregate collection. Our expectation was that the new method would enable more thorough validations and more detailed analyses.

The previous cancer statistics were designated as National Statistics. We labelled the new series as experimental because the method was new and subject to testing of quality and ability to meet user needs. Following a review of the statistics recently, I concluded it would be appropriate to remove the experimental label. Subsequently, we approached OSR to enquire about the process for designation as National Statistics. Your colleagues advised that the scope of the review already undertaken, and the
conclusions we reached, were likely to be a sufficient basis to grant National Statistics status.

In our review we investigated comparisons with the previous series; data coverage; data collection methods and quality assurance; user needs and feedback. We reached the following conclusions:

• The data are a complete record of known and recorded cancer activity. There is no known reason to suspect over or under coverage in the data and we judge the risk of any material impact on the aggregate statistics from coverage errors to be very low.
• The new figures for patients starting treatment were very similar to the previous series. This was the case at an all-Wales level, for Local Health Boards (LHBs) and at the level of tumour sites.
• Data are collected and processed by Digital Health and Care Wales (DHCW) and are signed off by LHBs. Whereas the previous data collections were supplied by health boards in aggregate form, the new data are collated by DHCW as patient level data. This helps to improve quality through more thorough validation, more detailed analyses and the ability to count patients and pathways separately.
• Key users reported that, although some further breakdowns would be helpful, the statistics are critical to understanding levels of activity and performance in cancer services. The users we have spoken to regard the data as credible and reliable.
• Along with other headline statistics in the high profile monthly NHS activity and performance statistical release, the cancer statistics receive a great amount of attention. They are a key source of information for journalists and are covered widely in the media each month, demonstrating the trust in which they are held and their value in informing the public.

Looking ahead, we intend to engage with a wider group of stakeholders to identify any unmet needs and improvements that can be made to the existing range of outputs. We will also continue to explore ways in which data quality can be improved further and whether additional breakdowns can be published.

My overall judgement is that the cancer services statistics are compliant with the Code of Practice for Statistics. They meet a range of user needs and key users regard them as credible, trustworthy and critical to their work. I regard this data as an improvement on the previous National Statistics for cancer services in Wales. On this basis, I believe the statistics meet the standards required for National Statistics and would like to request that you to consider awarding them this status.

With many thanks for the support your team has provided during this process.

Your sincerely

Stephanie Howarth
Chief Statistician, Welsh Government