In the State of New York we have found the key to interoperability for Healthcare Information Exchange (HIE) is in building on a services oriented architecture (SOA). The preferred SHIN-NY 1.0 architecture was based on SOA in order to get the benefits of its characteristics, which are having business focused services based on open standards that provide reusability, flexibility, agility, and loose coupling (abstraction). Abstraction is also one of the foundational concepts of computer science. In HIE, we want abstraction between providers and consumers of information; such that the provider does not have to know how the consumer wants the information and the consumer does not have to know how the provider sends the information.
One of our business goals is to make HIE a value-adding process for users in that it transforms between standards without losing the meaning of the content being shared. For example, what if a primary care provider (PCP) wants to send a referral patient summary to a specialist? In this case, the PCP only wants to select the data to be sent, find the specialist in his address book, and press send. He does not want to know, and even his computer system does not want to know, how the specialist receives the data. In this case, perhaps the PCP system is sending via Direct (a secure email containing health information). Perhaps, the specialist receives referrals as Notifications of Available Documents (an email containing a link to the secure HIE repository from where it can be downloaded). Fortunately, a good HIE can seamlessly transform between these and other standards without either of the users knowing it had to happen.
As described in the above example, the HIE works like the telephone network. When you place a phone call, you don't care what kind of phone the other person has and they don't care what kind you have. You can call from a cell phone and talk to someone on Skype or on a 50 year old rotary phone. Doing this provides syntactical interoperability so that one can know what you are saying.
Another example of such abstraction or loose coupling could be results delivery. In this case, an HIE can take a legacy message feed for lab results, translate a local code set into a common vocabulary, transform the message into a Direct message, and deliver it over open standards. This is a value add to the results provider who doesn’t have to change their system and a value add to the receiving medical records system in that they don’t have to support multiple legacy transactions with different mappings into their system.
In the results delivery example, the ideal HIE needs to work like the phone network as well as provide real-time language translation so that one person can speak in Spanish and the person on the other end can hear English. This is the value that a terminology service for vocabulary standardization or translation at the HIE adds to the process. This is what is referred to as semantic interoperability so that one not only knows what you are saying but they also understand what you mean.
This is how SOA for healthcare makes the clinicians and other staff interoperable, not just computer systems interoperable. This is the business focused characteristic of SOA. It starts with the business view of making the medical provider interoperable. Then, we provide processes and infrastructure to support that business.