Justin Chan ’12 – Computational Health Researcher

Justin is a PhD candidate working on creative computational solutions to reduce health inequity for millions of people around the world. He aims to do this through the creation of ultra low-cost medical devices that have the potential to democratise healthcare by testing for some of the most common yet manageable medical ailments at a fraction of traditional testing costs, without sacrificing clinical performance.

Name: Justin Chan
Graduating Year: 2012
Current country of residence: Washington, USA

Can you tell us a bit about yourself?

I studied in CIS from Year 7 to 13, followed by a bachelor’s degree in computer science at Dartmouth College, and a short stint working at Microsoft for a year developing software. I am currently finishing off my PhD in the School of Computer Science & Engineering at the University of Washington. 

A substantial amount of my work is focused on developing accessible solutions for medical problems where there are significant barriers to care and testing such as screening for new-born hearing loss using a smartphone, detecting middle ear fluid using active sonar and a paper cone, and blood clot testing using a smartphone. I am particularly interested in creatively repurposing commodity hardware and materials like smartphones, earphones, paper and plastic to develop frugal medical devices that can significantly reduce cost of medical testing by orders of magnitude, without sacrificing performance.

Below I provide a brief blurb of some of the really cool work I get to do:

1. My most recent invention is a $10 smartphone attachment that can screen for hearing loss in newborns. Unlike with adults, we cannot ask a newborn if they can hear acoustic tones because they simply cannot respond verbally! The cool thing here is that we can stimulate the cochlea (inner ear) with sounds from our probe, to automatically produce soft sounds known as otoacoustic emissions that are indicative of hearing health. Our device was evaluated across three clinical sites and achieved comparable clinical accuracy to a $6000 FDA-cleared device. We have set up an international group of clinicians and government officials in Nairobi, Kenya with the goal of enabling universal newborn hearing screening (https://tune.cs.washington.edu/).

2. Another huge problem in the area of paediatrics is middle ear infections which are the single biggest cause of healthcare visits for children. Many of these complications are preventable if middle ear fluid is detected early, but accurate detection is difficult as the fluid resides behind the eardrum, which can be difficult to visualise with an otoscope. I developed an accessible smartphone-based tool that sends sounds into the ear through a paper cone, detects the reflections coming off the eardrum and classifies whether there is fluid reducing the mobility of the eardrum. In a clinical study, our device obtained comparable performance to specialist tools that would have required long wait times for parents to get access to. In contrast, our device is easy enough to assemble and use by parents in the comfort of their homes, without any tradeoff in screening accuracy. 

3. The final project I want to mention is a smartphone-based tool to detect blood clotting times. People with heart conditions often take blood thinners which, in the wrong dosage, can create blood clots that lead to stroke or a heart attack. Frequent monitoring of clot times typically requires lab testing or expensive devices. The device I invented uses the vibration motor on a smartphone to vibrate a small cup containing just a drop of blood, and a small copper particle. We attach the cup to the smartphone using a custom plastic attachment. When the blood is still in liquid form, the smartphone’s vibrations cause the copper particle to move and rotate around in the blood sample. But as it coagulates, the blood becomes viscous and slows the movement of the copper particle to a standstill. All these changes can be monitored by the smartphone camera, which can process the video and automatically calculate clotting time. The device has the same accuracy as laboratory equipment, and only requires a few cents for the test equipment aside from the smartphone, which can be bought second-hand.

Are there applications of your research outside the developing world?

I have had the opportunity to develop several really interesting systems to tackle challenging public health issues that are prevalent around the world. During the onset of the COVID-19 pandemic lockdowns, I worked with researchers, volunteers, and engineers at Microsoft round the clock to design and build a contact tracing solution from the ground up that could be downloaded by millions of people. Unlike other projects I had worked on, this work was significantly more time-sensitive as even small delays in the project would have tangible effects on public health. In under a month, we designed a set of privacy sensitive protocols (PACT) for Bluetooth and GPS-based contact tracing, and developed an open-source implementation that was presented to Microsoft leadership as well as other universities. I learned a lot about the need for leadership and decisive action during this time as one of the lead contributors of the system. It was very gratifying to see that these efforts were adopted by the Washington State Department of Health as part of official efforts to combat COVID-19 (WA Notify). The app continues to be maintained at the University of Washington.

What inspired you to work in the area of computational health?

Healthcare is an area that affects everyone around us. Many of the issues I have worked on including hearing loss is an ailment I see even in my own immediate family. However, there are often many barriers and inequities in the healthcare system that make it difficult to obtain appropriate healthcare, even for those who are financially privileged. That motivated me to find a way to use computing and my background in a way that would have a significant and immediate effect on alleviating health inequity around the world. 

Can you give us a sneak peek into the thought process that goes into your research projects?

A PhD in computational health is like a dream come true: I basically have the intellectual freedom to brainstorm and test several cool ideas every year that can potentially improve the lives of millions of people. I get to work with some amazing people every day. Inspiration often occurs in the midst of vigorous debates with colleagues, and frequently at a point in a discussion where it seems as though we have painted ourselves into a corner. But the more we wrestle with a research problem, the more the nature of the problem is made clear, and magically inspiration seems to materialise. It’s great to be able to engage in these discussions several times a week.

What’s your workspace like, and why does it work for you? 

I have worked on quite a large range of projects during my PhD outside of health including, of all things, underwater acoustic communication using smartphones, and so my workspace is constantly being reinvented to suit the particular task at hand. During the earliest stages of a project, I’m often at a workbench, feverishly cobbling together a hardware prototype from spare parts. When it comes time to test a prototype, I can be anywhere from a hospital, to a swimming pool or an anechoic chamber running experiments. And finally when it is close to a paper submission deadline, I go through several rounds of editing at a desk surrounded in a whirlwind of drafts and related papers.

What have been your biggest learning experiences working in the medical field?

Technologists, engineers and inventors are in a prime position to innovate and enact positive change in the world. However, this often requires leaving the comforting bubble of technology and engaging deeply with people in other fields such as medicine. It is important not to hold oneself back from approaching problems because of one’s lack of background in a particular domain. If a problem is important, the work to get up to speed with the norms, jargon and state of the art in a given domain will be worthwhile and satisfying.

Other than tech and healthcare, which other industries would you like to have taken a stab at?

I would have gone down the arts and design route. Up till Y11 I had an equal interest in film studies and computer science, and decided to go down the tech route when forced to come to a decision about what subjects to take. I don’t really have any regrets about this though because the field of computer science is so broad that I feel I am consistently able to exercise both the creative and analytical sides of myself in the projects that I take on.

Quickfire round – give us the first answer you think of

  • Your guilty pleasure TV show: Shark Tank
  • Favourite toy as a kid growing up: LEGOs
  • Would you rather travel to the past or to the future? The future. I am probably too spoiled by the conveniences of the 21st century to be able to make it through the middle ages.
  • What were you afraid of as a child? Physical education class

Favourite memory from CIS?

The class of 2012 was pretty rebellious. I had at one point written an essay for English class that instigated a courtyard protest in reaction to the excessive amounts of homework and stress that were piled on top of us around Y10-11. This eventually led to greater coordination amongst teachers to stagger the times at which assignments were issued and reduced the likelihood of overlapping deadlines.

Sometime later, one of the school administrators instituted a highly controversial policy banning backpacks in classrooms that was met with quite a bit of pushback. I recall writing a computer program to scrape the online directory for hundreds of parent emails, which allowed for the wide distribution of a petition that aimed to apply pressure to the administration and ultimately succeeded in repealing the rule. The entire six-month saga helped me to forge strong bonds with some of the other student organisers and I still talk to them to this day though not about bags obviously.

What do you miss most about Hong Kong?

The city of Hong Kong is inextricably tied to all my formative childhood and adolescent memories. I will remember the walk up and down Braemar Hill everyday, the rush between tuition centres in Causeway Bay, and the late nights with friends under the glow of neon lights surrounded by 100-storey skyscrapers in Central. 

I try to travel to Hong Kong every 1 or 2 years to visit my parents who still live there, and I find that small details in the environment tend to bring back a lot of memories about my past life there. But as life goes on, and the speed of urban development in Hong Kong quickens, I find that many landmarks I used to remember are quickly replaced or remodelled. That being said, I am happy to see that the CIS campus continues to change and grow with the times!