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Open Source Software Hosting for Public Health

Introduction

HLN Consulting, LLC (HLN), a leading public health software application developer, has been at the forefront of Open Source software development, use, and support for public health. This has encompassed both the deployment and support of third-party Open Source products for our clients, and especially the development of new Open Source solutions. Since the vast majority of HLN’s work is government funded, software development activities conducted under “work for hire” agreements with government agencies often leads to public-private collaboration that results in Open Source products.

CDS for Immunizations (CDSi)

Much of HLN’s Open Source work has been related to clinical decision support (CDS). Though HLN has worked on several products, the one with the broadest appeal is our Immunization Calculation Engine (ICE) and related tools and utilities which were originally developed with funding from the New York City Department of Health and Mental Hygiene (NYC DoHMH). Though NYC retains the copyright to these products, the agency graciously released this software into the Open Source community under a GNU Lesser General Public License (LGPL) version 3. From 2012-2015, HLN invested a significant amount of its own effort into developing and improving the software and related knowledge artifacts.

The software actually consists of two major components:

• The ICE Web Service evaluates a patient’s immunization history and generates the appropriate immunization recommendations for the patient. The web service is implemented using OpenCDS, a general-purpose Open Source CDS platform. A limited set of patient data is sent to the web service, and a response is sent back to the original requester.
• The Clinical Decision Support Administration Tool (CAT) is a web-based GUI tool that enables subject matter experts to manage ICE rules and configuration without the intervention of software developers. CAT is still under development and is being released in a modular fashion as features become available. The first CAT module to be made available will be the Test Editor which enables subject matter experts to create, store, and manage test cases. The second module will be the rule authoring tool. CAT is not required for the ICE web service to run but is used to update its configuration; it does not contain or manipulate any patient data. CAT can run on the same server – or a different server – as ICE.

Considerations for External CDSi Hosting

HLN’s CDSi services and tools can be hosted within an organization or externally. Externally hosted services may provide some distinct advantages for organizations, including:

• Reduced barriers of entry for new users. If offered as a “one stop shop” a hosted solution could allow an organization to begin using the services more quickly than if the organization hosted the service on its own. For some organizations this is simply an easier solution to implement.
• Hosting of core service and tools are separable. Organizations can make independent decisions about hosting the core CDS service (ICE) and its administrative tools (CAT) with little dependence of one strategy on the other.
• Relatively lightweight products to deploy. The ICE service is a relatively lightweight service; CAT a relatively lightweight tool. Deploying these with modest service level expectations would not be too difficult nor too expensive, though more scaled service level expectations may present additional requirements.
• Secure (even HIPAA-certified) cloud service providers readily available. There are several reputable and reliable cloud service providers to choose from, though Amazon Web Services (AWS) is likely the most advantageous.
• Less responsibility over runtime environment. External hosting allows an organization to seek outside help to support its runtime environment, including debugging problems.
• Avoids additional regulation. External hosting passes much of the additional privacy and security regulation compliance to the hosting service provider, though the organization bears ultimate compliance responsibility.
• Avoids additional diligence and effort on security. Whether HIPAA is relevant or not, the hosting provider and not the organization ensures that the service is secure and defended against attack both upon its data and its service capability. External and repeated audit of the service and its platform is usually provided.
• Avoid distraction from other more crucial activities. With limited staff, using an externally a hosted service might serve to avoid distraction by the organization from more important activities more central to its mission.

Several hosting models exist for CDS products depending on the profile and needs of the organization. This table describes the likely hosting needs of different types of customers (Adapted from Arzt, N H, “Clinical Decision Support for Immunizations [CDSi]: A Comprehensive, Collaborative Strategy,” Biomedical Informatics Insights, Suppl. 2, October 2016):

	Hosted
	ICE	CAT
Immunization Information Systems (IIS) Immunization evaluation and forecast is a CDC Core Functional Standard.	Some IIS are looking for a turnkey solution that involves little effort or expertise on their part. Others may be concerned about performance with a remotely-hosted service. Some agencies might not permit external hosting by policy.	While most IIS have the expertise and interest in defining and even maintaining their own rules, CDC and AIRA are pressing for increased standardization making shared rules more attractive if ACIP and CDC CDSi-compatible.
	This might involve an IIS deploying its own Web Service but relying on HLN to configure it and manage the rules, or offer other ad hoc assistance.
Other Public Health Agency (PHA) PHAs might want to use CDSi for data analytics including up-to-date calculations for individual patients and whole populations.	Most local PHAs likely want a turnkey solution as they do not have the informatics expertise to deploy or maintain a web service. Some agencies might not permit external hosting by policy.	Local/state PHA with strong informatics capability may want to manage a software service and its rules on its own.
	This might involve a PHA deploying its own Web Service but relying on HLN to configure it and manage the rules, or offer other ad hoc assistance.
EHR-S Vendor CDS is a major area of functionality and most general-purpose EHR-S do not do this well, especially when it comes to pediatric functions.	Most EHR-S vendors would likely want to run and maintain their own Web Service. Some might want a fully-hosted service, but would likely require a rigorous service level agreement and a reliable, scaled solution.	Many EHR vendors are less interested in maintaining their own rules so long as they are assured of ACIP compliance.
Academic Medical Center Many have developed and deployed home-grown EHR-S.	Those with strong informatics programs may just want to do it themselves. They also tend to be familiar with the open source model. Those with less capable informatics programs may want some level of assistance all the way up to a turnkey service.
Accountable Care Organizations (ACO)/ Patient Centered Medical home (PCMH) ACOs have high expectations placed on them especially for analytics and often little infrastructure to produce results quickly.	Uncertain of how sophisticated any ACOs might be. ACOs are more likely to need more services rather than fewer.