It is in the news that UK NHS patients will not be given the option of whether their medical data is processed by US spy tech firm Palantir. This is being justified by because their data will be anonymised before it is shared.
I have done a little work on anonymisation in biomedical research, and it is a difficult problem. The data a biomedical researcher is interested in is usually inherently personal and identifying, at least in the GDPR sense of the word in that it can be used with other data to identify an individual. There is always a tradeoff between the utility of the data and the risk of deanonymisation. This paper (or avoiding the paywall) gives an idea of the maths that can be applied to this problem to define the extent of the risk of individual personal data exposure.
Has the method and parameters used for anonymising NHS data before it is sent to Palantir been published? Is the likely or acceptable risk of deanonymisation quantified?