NCHEX HIE Model
Health information exchanges typically utilize either a centralized or federated model for storing patient data. In a centralized model, all patient data is stored in a central location and queries to the HIE are typically quick, but this type of model has a few drawbacks. For example, storing data in one location creates a single point of failure for the HIE, and multiple points of failure for all of the providers who rely on the central repository to add, view and edit patient data. A federated model stores all patient data in each provider's EHR and is usually tied together using an enterprise master patient index or locator in a shared environment. This type of model spreads the risk that a central failure could disable the entire HIE, but the downside is that queries to the HIE must traverse all the EHRs in the system and limits the scalability of this type of HIE.
The NCHEX HIE architecture uses a hybrid model that collects a limited amount of information from hospital and physician practice EHRs and stores it in a secure data center where it is processed. Queries to the HIE do not touch a provider's EHR and therefor will not effect the performance or security of the individual EHRs. By combining certain aspects of the centralized and federated HIE, our hybrid model provides speed, security and scalability. The following diagram illustrates how NCHEX data is collected from the existing NCHESS interface engine (orange) and is fed to the HIE data center, the provider's clinical systems and to the administrators and other participating providers (green).
Providers query and receive results through a "virtual single patient record" (vSPR) that is dynamically assembled by NCHEX from all participating providers' EHRs. Queries and results may be displayed through a providers EHR or using a secure Web browser. NCHEX does not require a provider to have an EHR, but it will integrate with many existing existing systems if they do, including:
Physicians may also use a secure Web browser to view the same patient data from home as they can from a hospital or physician practice.
Click on the images below to view sample screenshots.