Development and Implementation of an Expert Information System ...

CLIN. CHEM. 41/9, 1333-1337 (1995)

#{149} Oak

Ridge Conference

Development and Implementation of an Expert Information System (BRITE) Used in Technical Support of Medical Diagnostics Customers Thomas

Hopkins,’

Ramesh

Advani,

and Garry

Gudmunson

We developed BRITE (Bringing Resources and Information to Employees), an expert information retrieval system, for problem solving and retrieving technical product information. Specialists in our Technical Assistance Center (TAG) use the BRITE system on a Pentium workstation to access information in 200 000 customer calls per month.2 The TAC technical specialists are responsible for support of multiple products, including automated random-access immunoassay systems and critical blood analyte/blood gas systems. The breadth of products these specialists are able to support has been limited by their ability to maintain a high level of expertise on those products. In 1991, the first fully automated chemiluminescence assay system, the ACS:180#{174}, was

released by CCD. The complexity of this new product led CCD to pursue relatively new technologies so that customers would continue to have a high level of technical support. To better meet the customers’ needs and keep current with rapid advances in laboratory automation, CCD developed the BRITE (Bringing Resources and Information to Employees) expert system. Technical support in the medical diagnostics industry depends on several factors: speed, accuracy, and efficiency in the delivery of information to the laboratorian or clinician. One technology that has gained rapid success in the capture and preservation of com-

plex information is computer-based intelligence. This technology of expert systems, also called knowledgebased systems, was built to solve problems in engineering, molecular biology, manufacturing, computer design and signal processing, and many other sciences. Now we are using expert systems to help meet the technical support needs of the laboratorian who is looking for accurate and reliable support for medical diagnostics

instrumentation.

There are three basic criteria for selecting a computer-based knowledge system: First, the specialized or “expert” knowledge exists in an organization but is not readily accessible; second, individuals at geographically diverse locations need to possess this knowledge at all times and be able to recall it instantaneously; finally, technical knowledge is complex but can be organized for computer automation. The area of technical support meets these three criteria readily: Expert” knowledge generally resides with scientists and engineers in research and product development, yet the technical support personnel, who are expected to respond immediately to a laboratorian calling an organization for assistance, must be able to rapidly obtain the requested information from their knowledge base. This knowledge tends to be complex and extensive but is capable of being encoded for a computer system. TAC specialists at CCD now use the BRITE system to better meet the laboratorian’s technical support needs by obtaining and conveying the “expert” knowledge and information rapidly, accurately, and efficiently. “

Materials

and Methods

A team of experts contracted to extensively evaluate the multiple TAC locations and analyze the different needs for information at these sites identified three target areas of informational needs: the expert system component, the document retrieval component, and the database component. The expert system component provides the advisory/troubleshooting capability of the system. The document retrieval components allows access to all product-related printed material. database component dynamically supports both

bleshooting and document retrieval requirements. These three components, and the graphical user interface (GUI) technologies used to integrate them, form the foundation

Ciba Corning Diagnostics, Norwood, MA 02062-4694. ‘Author for correspondence. Fax 617-551-7714.

2Nonsdard

TAC, Technical

abbreviations:

CCD, Ciba Corning Diagnostics;

Assistance Center; CBR, case-based reasoning; GUI, graphical user interface; WAN, wide area network; LAN, local area network; and ODBC, open database connectivity. Received May 5, 1995; accepted June 16, 1995.

The trou-

of the BRITE

system.

Expert System Component In developing an expert system that would troubleshoot all major product lines, the tool chosen had to be robust, easy to use, and capable of handling both simple queries and complex troubleshooting. The types CLINICAL CHEMISTRY, Vol. 41, No. 9, 1995

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of expert systems analyzed were case-based reasoning (CBR) tools, rule-based reasoning tools, decision trees, and neural networks. Because no one tool is best for all applications, the nature of the particular problem to be solved had to be analyzed critically. The tool chosen by CCD was a CBR shell built on a rule-based algorithm. CBR tools are designed to retrieve known problem solutions. CBR compares the current troubleshooting session with known problem solutions. According to the answers to natural language questions, the tool assigns probability factors (weights) to each case. The weights of these cases increase or decrease depending on the answers to specific questions. Using these weights, the TAC specialist is able to identify which case best matches the customer’s problem. One of the strengths of CBRs is that questions do not have to be answered in any particular order (unlike structured tree-based systems).

Examples. A customer reports a problem with the printer on an instrument, which outputs reports with smudged print. A decision tree and a CBR would provide the same summary of potential solutions with a probability statement for each: Possible causes of smudged print:

1) Bad ribbon

60% probability

2) Damaged print head 30% probability 3) Wrong paper 10% probability In addition, however, the CBR tool also has a set of questions associated with each possible solution so that the list can be narrowed.

For example,

the CBR system

might ask, Does the print have blank spots? A no answer would eliminate or reduce the probability of the ribbon as a possible solution and increase the probability of a damaged print head as the solution (1).

Pattern-matching

capabilities

give another level of

troubleshooting solutions. For example, if a customer calls in with a problem in which a specified chemistry analyzer gives discrepancies in results for three analytes while performing well for the remainder, the pattern-matching system searches for similar characteristics about these analytes. By ruling out such common areas as sample size, washing sequence, reagents, etc., its search is quickly narrowed to specific areas. If CBR alone were used to perform these tasks, tens of thousands of cases would have to be built to account for all possibilities. Rule bases that allow pattern matching are extremely powerful; however, they are more difficult to maintain and are used only when complex inferencing is required. The CBR tool is easy to maintain and expand. Cases that are not resolved by the system are identified by the system, and the resolution to these cases is added to the system in a “knowledge acquisition” process. The first step in developing the knowledge acquisition process was to identify a knowledge engineer to

develop the cases and rules. The knowledge engineer must have extensive experience with expert systems technology and its application to the diagnostics field. To meet the requirements and achieve all the goals identified, the knowledge engineer must be able to 1334

CLINICAL CHEMISTRY, Vol. 41, No. 9, 1995

define the optimal (2).

structure

and programing

language

Knowledge engineers at CCD elicit and assimilate knowledge from experts effectively and then translate that knowledge into efficient cases and rules. It is extremely important that the knowledge engineer have a high degree of domain-specific knowledge to be able to communicate effectively with the scientists and engineers. The development and maintenance of expert systems differ from typical production systems. Whereas typical production systems have a lengthy development cycle, with minor modifications once implemented, expert systems have a much shorter development cycle and are constantly being refined and updated as changes are needed. The knowledge engineers develop cases from the scientists and engineers and then enter them in the system. Because knowledge contained within the expert system is constantly evolving, the system is implemented with a small knowledge base and the ability to increase that knowledge base daily. This process happens in three stages. First, the TAC specialist, through use of the systems, identifies those cases that are not in the knowledge base. Second, all cases not in the knowledge base are sent to a designated individual who identifies the appropriate troubleshooting expert. Third, the knowledge engineer acquires the expert’s troubleshooting methodology used for those cases and enters them in the system. The

knowledge that is entered is controlled by the TAC specialists’ use of the system. This ensures that the knowledge entering the system is relevant to current troubleshooting needs. At present, the system includes thousands of cases covering all major product lines for CCD. This is an ongoing process that continues throughout the life cycle of the product. Document Retrieval Component The information component of BRITE consists of the published information that TAC specialists require to support customer inquiries, e.g., customer and service manuals, technical bulletins, parts lists, and development literature. The source information required by the document retrieval component resides in a variety of different formats and on various different platforms throughout the organization. Each department that creates and maintains this information has independently developed systems and procedures (e.g., word processing,

desktop

publishing)

that

meet

specific

needs. To provide a common interface for viewing all of the various documents, it was necessary to select tools that allowed importing from all of these applications and platforms. Although scanning is often used to convert documents into electronic media, the end product so obtained has several shortcomings, including large file size, layout deviations from the original

document, and poor graphics quality. CCD, therefore, decided to pursue portable document technologies that had recently become available. The document retrieval component had to be able to import documents from

Integration

native applications and platforms and display them in a common interface, using software that needed only easy maintenance and minimal manual intervention. Various packages offered by vendors (e.g., Adobe, Caere, Farallon Computing, No Hands Software, and Verity) were analyzed and evaluated for their particular strengths and weaknesses (3). The document retrieval component chosen takes postscript files and converts them into portable documents, which are then accessible by the TAC specialists through the workstations. CBR then provides a search engine across all documents, and indexes and hyperlinks allow for rapid navigation through them. Most documents and all manuals that are in the information system are under process document control, and updates to the BRITE system are automatic. When CBR is used for troubleshooting, documents are embedded in the case base to support the troubleshooting process.

Visual C + +, Gupta, and Visual Basic are examples of GUI tools. Retrieval of all information must be integrated so that the TAC specialist can perform the customer technical support without exhaustive computer skills. Use of GUI technology allows a rapid response time of s3 s, which confers a “seamless” appearance to the response of the TAC specialist. GUI tools are used to build and maintain the BRITE manager. The BRITE manager, which is the user interface for the TAC specialist, acts as the focal point to all applications within the system (Fig. 1). The expert system component is interfaced by using dynamic data exchange. The document retrieval component is interfaced by using object linking and embedding. The database components are interfaced through standard query language (Fig. 2). Legacy mainframe application systems accessed through BRITE (e.g.,call tracking and order entry) are accessed through the BRITE manager by use of dynamic data exchange. These applications are automatically opened by the BRITE manager as required; they can also be activated individually by the TAC specialist as needed. Administrative tools such as central local area network (LAN) fax and word-processing software are utilized to fax documents such as package inserts directly from the TAC specialist’s workstation to the customer. For example, when a customer calls the TAC with a problem on an ACS: 180, the TAC specialist goes to the BRITE manager and opens the ACS:180 case base (Fig. 1). The description of the problem is then entered into the system, and a series of questions related to particular cases appear. The answers to these questions will change the probability factors displayed to the left of the cases. BRITE is structured such that when a probability is >90 the color of that case changes; the TAC specialist retrieves that case and displays the

Database Component As with the information component, the data required for customer service exists in many locations and on many platforms. These data had been previously available to the TAC locations through printed documents. The data originate in the manufacturing, product development, and statistical service departments in multiple facilities, with the databases and database types being selected by these departments based on their different individual requirements. The BRITE system can receive these different databases through the wide area network (WAN) and convert them to a relational database that is open database connectivity (ODBC)-compliant. Using a non-ODBC database requires that each database be processed individually. ODBC-compliant databases allow other departments throughout CCD to access these databases without individual processing.

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Fig. 1. Schematic of the BRITE manager used to integrate expert system, database, and document retrieval components. dR. cases in review. CLINICAL CHEMISTRY, Vol. 41, No. 9, 1995

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BRITE

System Overview

computer configured with 16 Mb of RAM, a 500-Mb hard drive, and a 20-in. monitor. Daily updates are done on1 each LAN via a data replication batch process over the WAN. Results The BRITE lines,

system, encompassing

was fully

all major product

in all CCD TAC locations

implemented

in August 1994 Each TAC specialist received 3 days of training, which included computer skills and BRITE system skills. The process for updating the system has been incorporated into standard operating procedure within the TAC groups, and the case base has grown from 200 cases initially to >3000 cases as of April 1, .

1995.

Fig. 2. Representation of the basic integration techniques used in the BRITE development process and in the GUI development. DDE, dynamic data exchange; OLE, object linking and embedding; SQL, standard

query language.

the product

action to be taken by the customer. This information is attached to each case and is retrieved with one keystroke (Fig. 3). At this time, any supporting documents or requests for information can be accessed through document retrieval (the information case base) and instantly faxed from the workstation. Platform and Infrastructure The BRITE system resides on a Novell (Sunnyvale, CA) token ring network (Fig. 4). Multiple users at multiple sites are connected through the CCD WAN. Each workstation is attached to a LAN with a Pentium personal

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Several other applications for BRITE have subsequently been implemented throughout the company. In the manufacturing plants, the BRITE system is used in the engineering departments and on the production floor. Manufacturing engineers use the BRITE system to access databases and contribute to the development of new cases. On the manufacturing floor, new cases are identified and added proactively to the system. In a pilot program, BRITE is being made available to all field employees, including applications specialists and field service engineers. The pilot will address logistical issues such as the BRITE update process, remote access, and hardware requirements as well as security requirements.

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identified and prioritized by the TAC specialists. The time required for a new TAC specialist to become proficient in customer technical systems has been reduced by 50%, and the support for new products has been substantially improved by continual expansion of

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Fig. 3. Example of the BRITE ACS:180 case base being used by a TAC specialist to solve a problem from a customer calling in with a luminometer error message 1336 CLINICAL CHEMISTRY, Vol.

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BRITE

Information

Highway

Fig. 4. CCD’s nationwide WAN infrastructure to facilitate information transfers that develop and update BRITE.

The benefits anticipated for the field employee include on-line troubleshooting assistance, documentation retrieval, and database access. These benefits are similar to those provided to TAC and will give the field service organizations ready access to improved troubleshooting techniques and problem resolution. The primary beneficiary of the BRITE system is the CCD customer, the laboratorian. Response time to customer inquiries and requests for information has decreased by -30%. Moreover, customers receive consistent troubleshooting information, regardless of which TAC specialist the customer contacts. The central electronic fax server has improved the ability to both send and receive information from customers. In the near future, components of the BRITE system will become available to all CCD customers, both directly through instrumentation and via remote access. Discussion The BRITE package that

expert system was created as a software could dynamically be changed and up-

dated. After the goals were identified and the tools were chosen, the three components of expert system, document retrieval, and database were integrated into a state-of-the-art single application system. BRITE adheres to information retrieval standards and common connection protocols. All new and future databases are constructed on relational databases that are ODBC-compliant. Older (legacy) databases are being rewritten to adhere to these standards, and the BRITE system will eventually interface directly to these databases without requiring manual intervention. Industry standards such as ODBC are being used to expand BRITE so that communication is facilitated. In summary, changes in the medical diagnostics industry necessitate the ability to transfer information efficiently. Access to public and private networks such as the Internet has increased dramatically in recent years. The architecture of BRITE allows for the transfer of components of the system directly to the laboratonan. The extension of this technology to customers in the laboratory and personnel in the field provides the ability to capture and dynamically incorporate information. BRITE is a tool that will expand to retain current knowledge and integrate future knowledge. Editorial and technical critique of this manuscript was provided by Julie Williams, Chris Poulin, Peter Harrington, and Rawson Cowen, and Rebecca Davis of Ciba Corning Diagnostics.

References 1. Pepper J. We’re off to seize the wizard: the revolution in service automation, 2nd ed. Verona, PA: Service Ware Inc., 1993:1.4:24-25.

2. Clanon J. Guide to knowledge engineer selection. Digital Equipment Corp., 1985:5-6. 3. Felici J. Breaking the ties that bind. Windows Sources 1995; 3:116-40.

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