Project Proposal : LabVis

CPSC 533 - Information Visualization

Adam Bodnar and Dmitry Nekrasovski

bodnar@cs.ubc.ca dmitry@cs.ubc.ca

March 1, 2004

Overview

The goal of this project is to develop an effective visualization for displaying and interacting with medical laboratory results.

Motivation

Current methods of reporting and interacting with medical laboratory results consist of text and numbers, which can be printed out or displayed monochromatically. While such a technique is sufficient, it does not take advantage of advances in both computer and visualization technology, which could lead to increases in efficiency, and help in the process of teaching medical interns the process of diagnosis [3].

Domain, Task, and Target Data Set

This project lies in the domain of laboratory medicine, the medical specialty that deals with all aspects of performing and interpreting laboratory tests. Current techniques for displaying and interpreting laboratory results are sufficient for senior clinicians who practice in a variety of specialties, but for medical students and interns, the challenge of interpreting appropriate laboratory tests can be enormous [3].

The task is to display a series of interactive, effective visualizations that illustrate the results of laboratory tests. For the purposes of this project, the visualization will involve the results of  a thyroid function test, which is commonly used to diagnose disorders of the thyroid gland and also to monitor the effects of treatment of known thyroid disease [2]. The common analytes measured by a thyroid function test are free thyroxine (FT4) and thyroid stimulating hormone (TSH). In addition, optional supplementary analytes that may also be measured when FT4 and TSH levels are outside the normal bounds include thyroxine (T4), free triiodothyronine (FT3), and anti-thyroid peroxidase antibodies (anti-TPO) [1].

The target data set is a time-series of approximately 1500 thyroid function tests, all of which include FT4 and TSH results. Some of the tests also contain measurements of T4, FT3, and anti-TPO. Most patients whose tests are included in the dataset have been tested multiple (up to 15) times.

Personal Expertise

Aside from watching multiple episodes of NBC's hit medical drama E. R., we are not familiar with the area at all, but feel that this will be an interesting and practical problem to solve using visualization techniques.

Proposed InfoVis Solution

We propose LabVis, an interactive system for displaying medical laboratory results. The LabVis system is made up of three different, but linked, visualizations aimed at providing the user with both an overview of patient test results through time and specific information for one or more tests. These are illustrated in the diagram below. The first visualization offers a time-series based overview of FT4 and TSH laboratory test results for a specific patient. The normal ranges of each analyte will be highlighted. A secondary visualization displays a scatterplot of FT4 vs. TSH, and is used to interpret selected test results chosen by the user based on the primary time-series overview. Again, highlighting is used to indicate those areas which lie outside the normal range. A third visualization displays the numerical test results, as well as supplementary laboratory test data. As with the primary time-series visualization, highlighting is used ito indicate those areas which are abnormal and require immediate attention. A different type of highlighting is used to link the visualizations by denoting the test results currently selected by the user. Together, these linked visualizations provide decision support for the physician by displaying an overview of patient laboratory results, along with supporting details-on-demand interaction to aid the physician in making a diagnosis and monitoring patients for possible abnormal medical conditions.

Scenario of Use A clinician enters the patient number of a patient in the dataset, and is presented with the three visualizations shown on the right. The clinician inspects the first (time-series) visualization and notices that, while the patient's thyroid test from February falls into the normal ranges of both FT4 and TSH, his/her most recent TSH sample doesn't fall into the normal range. The clinician selects the most recent set of tests, which is then highlighted in red in all the visualizations. The clinician inspects the second (scatterplot) visualization and observes that the highlighted test results fall into the range of possible T3 toxicosis. To confirm this diagnosis, the clinician requires a measurement of the FT3 analyte. The clinician refers to the third (numerical) visualization, observes that the highlighted test results do not include a FT3 measurement, and orders an FT3 test to be performed on the patient.

Proposed Implementation

LabVis will be implemented using Java. The InfoVis Toolkit will be used to provide time series and scatterplot drawing functionality required for the appropriate visualizations.  

Project Milestones

1. Send Dr. Wes Schreiber a copy of this proposal and get his feedback
2. Experiment with the InfoVis Toolkit
3. Create a prototype of each visualization view separately
4. Integrate prototype together and enable interaction
5. Demonstrate LabVis to Dr. Wes Schreiber and get his feedback
6. Perform final user evaluation

References

1. Great Smokies Diagnostic Laboratory, GSDL Comprehensive Thyroid Assessment, Asheville, NC, USA, 2002.
2. Jones, G. Thyroid Function Tests. The Pathology Service of St. Vincent's Hospital, Sydney, Australia, 2000.
3. Schreiber, W. Interpretation of Laboratory Tests in Real Time with Real Patients. Hand-Out, Department of Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, Canada, 2004.