The NHS has since backed off from this stance and now allows an opt-out policy. That's still a far cry from the opt-in approach taken by MAeHC, and in the context of a burgeoning US movement toward "personally-controlled" health data management, it's downright archaic.
The latest report is that despite this change in policy, physicians themselves are rebelling against the system: 2/3 of NHS family physicians say that they will boycott data-sharing in the system according to a recent poll (see Family doctors to shun national database of patients' records). In a country where individuals have historically deferred to the government on issues of information access, this is a pretty stunning development.
Our policy in the MAeHC project is to allow patient opt-in, meaning that no information will be made available to other entities without the specific permission of patients. Our current opt-in rate is about 93%.
While an opt-in approach clearly has some short-term risks -- such as, slower adoption of systems by physicians, delays in achieving the benefits of clinical data-sharing -- it provides a firmer foundation for the overall enterprise. In the end, we won't be able to reap the benefits of clinical integration unless we build systems that both patients and clinicians can trust.