Automatic Tracking Technology

Client

All of PCTS's tracking systems operate as web applications accessible via Internet Explorer 5.5 or higher (IE 6 is recommended) on 32-bit Windows clients (Windows 2000 or XP are recommended). We can also deploy selected, customized data views and simple data-entry screens to handheld Pocket PC devices using the embedded version of IE.

Network

Although transporting web content over any TCP/IP connection is technically feasible, our systems are optimized for network speeds of 10 Mbps and higher. As with all web applications, higher network speeds generally produce better performance. We support both wired and wireless networks.

Server Components

The server-side portion of the tracking system relies on standard Microsoft components, including:

Windows 2000 Server (Standard or Enterprise Edition)
SQL Server 2000 (Standard or Enterprise Edition)
.NET framework version 1.1
Internet Information Services (IIS)
Active Server Pages (ASP)
ADO 2.6
ADO .NET

Data Transport and User-Interface Generation

The system uses standard ASP pages to generate all read-only views (e.g., spreadsheets and maps) that list and describe patients, staff, and other resources. Data-entry forms are implemented using a combination of standard ASP code, XML-based SOAP messaging, and client-side script: the ASP code draws the basic form, SOAP messages retrieve field values and listbox contents, and the client-side scripts process the XML result sets to populate listboxes and seed fields. Client-side scripts also perform initial data validation, package field values into XML payloads, and submit those payloads to the web service for processing and storage via SOAP messaging.

All SOAP communication from the web browser uses the XMLHTTP and XMLDOM objects included with Internet Explorer. The endpoints for SOAP messages are a series of .NET web services exposed through IIS as virtual directories of the tracking system's main web application.

Security and Auditing

All of our tracking systems developed to date rely on IIS challenge-response authentication and integrated Windows security features. By applying permissions to ASP source files and other non-ASP control files, we can secure entire screens-or even individual fields and features on those screens-at the user and group level.

All transactions that create, read, update, or delete patient data are audited at a very high degree of granularity. Specifically, we save every patient-related SOAP message to the database along with a timestamp, user ID, and message type code. Consequently, we can reconstruct everything that happened to a patient's visit in our system.

Interfacing

Our preferred interfacing method is HL7 over TCP/IP. We have existing interfaces that allow us to receive data from ADT, scheduling, and order-entry systems.

Our interface application (known as HITIS) can receive and parse all HL7 message types and all segment types, including custom Z segments. HITIS was developed as a multi-threaded, high-performance .NET Windows service that can listen on and process data from multiple ports simultaneously. Each port can support one or more message types.

We can also interface with non-HL7 systems using custom ASCII streams over TCP/IP, SOAP XML messages, ODBC, ASCII files, and serial feeds.