LifeFlow: Understanding Millions of Event Sequences in a Million Pixels

Lifeflow 3 visual

Project Description

Event sequence analysis is an important task in many domains: medical researchers study the patterns of transfers within the hospital for quality control; transportation experts study accident response logs to identify best practices. In most cases they deal with more than thousands of records. While previous research has focused on searching and browsing, overview tasks are often overlooked. We introduce a novel interactive visual overview of event sequences called LifeFlow. LifeFlow scales to any number of records, summarizes all possible sequences, and highlights the temporal spacing of the events within sequences.


While Lifeflow only handles point event data (i.e. with a single timestamp) EventFlow now also handles interval data, and provides advanced query capabilities.



We thank the National Institutes of Health (Grant RC1CA147489-02) and the Center for Integrated Transportation Systems Management (a Tier 1 Transportation Center at the University of Maryland) for partial support of this research. We also thank MedStar Health and Dr. Zach Hettinger, Dr. Phuong Ho, Dr. Mark Smith and Mr. David Roseman for their close collaboration.

Featured Presentations

If this is your first time here, go ahead and take a look at this presentation. It will introduce you to LifeFlow. (Video demo inside)
Other presentations can be found from this page.

Featured Videos

If you are in a rush, view only these two videos below. Within five and a half minutes, you should know much more about LifeFlow.
Other videos can be found from this page.


If you have already known enough about LifeFlow and would like to see more applications of LifeFlow in different domains, check out these case studies.

1. LifeFlow Case Study: How do people read children books online?

2. LifeFlow Case Study: Comparing Traffic Agencies' Performance from Traffic Incident Logs

Software & User Manual

LifeFlow is available to use in your projects, Please contact Catherine Plaisant ( with a description of your project to get a copy of the demo.

The online user manual is here.

Data Format

Please visit the data format page in the user manual for more details about the data that LifeFlow can receive as input.


While Lifeflow only handles point event data (i.e. with a single timestamp) EventFlow now also handles interval data, and provides advanced query capabilities.


The main Lifeflow paper i.e. If you are looking for a citation, please cite this paper.
Krist Wongsuphasawat, John Alexis Guerra Gómez, Catherine Plaisant,
Taowei David Wang, Meirav Taieb-Maimon and Ben Shneiderman
LifeFlow: Visualizing an Overview of Event Sequences
in Proceedings of the 2011 Annual Conference on Human Factors in Computing Systems (CHI'11), 1747-1756.

A case study: our colleagues at the Mayo Clinic show how they used Lifeflow
Cui Tao, Krist Wongsuphasawat, Kim Clark, Catherine Plaisant, Ben Shneiderman and Christopher G. Chute.
Towards Event Sequence Representation, Reasoning, and Visualization for EHR Data
in Proc. ACM SIGHIT International Health Informatics Symposium (IHI) 2012.

Another case study with log data
Jae-wook Ahn, Peter Peter Brusilovsky and Krist Wongsuphasawat.
Analyzing User Behavior Patterns in Adaptive Exploratory Search Systems with LifeFlow
in Proc. Workshop on Human-Computer Interaction and Information Retrieval (HCIR) 2011.

Early Lifeflow paper showing application with transportation data
John Alexis Guerra Gómez, Krist Wongsuphasawat, Taowei David Wang, Michael Pack and Catherine Plaisant
Analyzing Incident Management Event Sequences with Interactive Visualization
in Transportation Research Board 90th Annual Meeting Compendium of Papers, 2011.

Related Projects

Our original research on LifeFlow stimulated new work by other labs, such as OutFlow and CareFlow at IBM.

Summary of HCIL Projects in Temporal Visualizations:   LifeLines, LifeLines2, PatternFinder, etc.

Related Workshops from HCIL

Electronic Health Records Informatics (May 26, 2011)

Interactive Visual Exploration of Electronic Health Records (May 30, 2008)

Personal Medical Devices Workshop: Increasing Patient Healthcare Participation (June 3, 2004)

Web Accessibility