Imagine if you would, a world class clinical decision support system. How would it work? What would you see? Now imagine how that system would be integrated into an Electronic Health Record. How does it work? What does it do differently?
Now that you've imagined it, let me tell you about the trap that you just fell into. You've just imagined that CDS and EHR are separate components that can be integrated together. In reality, a world class clinical decision support system and world class electronic health record would be indistinguishable from each other. You wouldn't know where one ended and the other began. It's no longer about decision making and record keeping.
We usually think about CDS answering questions posed to it based on clinician interactions ... checking to ensure that the medication ordered won't interact badly with anything else that the patient is taking, for example, or picking the best antibiotic as the current point int time. The real way to think about it is much more clever, but also extremely difficult to work out.
What the system really needs to do is work collaboratively with the healthcare provider in ways that a) make his or her work more efficient, and b) address the myriads of details and minutia of medicine so that the provider can focus more on the patient in front of them. It is this attention to the provider experience with the system where we need to pay attention. It's not about doing the physician's work, but augmenting their abilities -- putting the right data in front of them, asking the right questions, and providing critical analysis across large volumes of data, all at the right time and in an easy to understand presentation.
It's a (workflow) optimization problem and a user interface problem. It's also a trust problem, because until the provider trusts a system to work with him or her, they won't ever use it to its fullest capability. There may even be something about the way we train doctors to use technology that may need to change before we'll ever be able to develop such a system. It's worth thinking about.