As communities begin to think about reopening in the United States, testing becomes critically important. Health officials will need to be able to track whether COVID-19 infections are decreasing and where outbreaks may reoccur. We sat down with David Miller, Verily’s Head of Biostatistics & Epidemiology, to go behind the scenes of Project Baseline’s community-based COVID-19 testing program. Dave shares how the program was designed in partnership with local and state governments and provides insight into the role testing will play moving forward. Here are his edited comments and a video from the conversation.

David Miller, Verily’s Head of Biostatistics & Epidemiology
David Miller, Verily’s Head of Biostatistics & Epidemiology

How did the idea for Project Baseline’s community-based COVID-19 testing program come about?

The first instinct among researchers at Verily was to do a clinical study, but we quickly realized over the course of just a couple of days that the most critical thing we could do as the pandemic started to take hold in the U.S. was simply getting people tested. Verily’s Baseline Platform has been in development for almost five years and was envisioned as a new approach to bridge clinical research and clinical care.

When public health officials were looking for a way to deploy smart testing programs, we realized that the flexibility that has been built into the platform was exactly what we needed to pivot from the study mindset to the care mindset. The goal has been to create a connected program to support individuals from screening through testing and receipt of their test results. Now, we are also beginning to conduct COVID-19 research through the Baseline COVID-19 Research Project. One of our first initiatives offered as part of the COVID-19 Research Project is Baseline Antibody Research. Initially based in the Bay Area, effort is focused on understanding the human immune response and testing for antibodies in those with a positive COVID-19 test. If you’re interested in joining, you can visit

Can you tell us more about why testing is so critical?

There’s a saying that you can’t fight what you can’t see and I think that’s so true with COVID-19. We can’t put the right measures in place unless we know where the disease is.

Testing is going to help us figure out when we can start to come out of all of this. If we're not testing people, we don’t know when the numbers are starting to come down. The testing data on the number of people who test positive and negative for COVID-19 is really essential. If you’re only looking at the positives, you don’t know if the rate of infection is going up or if there are just more tests being performed, so we systematically look at both.

What differentiates project Baseline’s COVID-19 testing program from other COVID-19 tests?

First, we have a dynamic online screener which collects information for public health authorities to help prioritize individuals for screening when testing resources have been scarce.

Also, this is a community testing program, not an in-hospital program. A lot of the numbers that have been reported were of people getting tested in hospitals, and that's a very different population than the people who were walking around with more moderate cases. We just don't get a full picture of the disease unless we’re doing this community-based testing and collecting systematic data on risk factors while we’re doing it.

Data is the great equalizer for getting people tested.  Initially, it seemed like people with highest priority to get tested were politicians or basketball players or celebrities. We don't have any questions about which sports you play or which movies you’ve been in. Recently, we’ve been able to open up testing to everyone public health authorities direct to our website.

David Miller interview thumbnailDavid Miller interview thumbnail
Watch the video interview with David on our YouTube channel

So how did you determine which questions would be asked in the screener?

I was involved with figuring out what questions we wanted to ask that best aligned with emerging public health guidelines from state and federal agencies. The online screener, for example, asks questions about your contact with confirmed cases, your symptoms, if you’re in a high risk occupation, and also if you have additional risk factors like congestive heart failure or diabetes.

When we first launched in coordination with the California Department of Public Health, public health officials needed to prioritize some individuals based on their ‘risk score’ as well as be sure those that are deemed eligible did not exceed the number of tests that were available at the open sites.

Early into the program we made a switch to the algorithm to prioritize certain factors a little bit higher based on changing guidelines and we needed to make sure that when we did do that switch, it didn't completely change how many people were coming to the testing sites. The screening questions helped prioritize individuals for scheduling based on site capacity. Recently, we’ve had sufficient capacity to test everyone who is sent to the site, but the screener data is still important to understand the longitudinal trends and to identify which groups may benefit most from testing in the future.

Can you tell us more about the changing guidelines you had to adapt the test around?

The CDC changed guidelines early on, placing more emphasis on people with symptoms, as well as health care workers, first responders, and people working in prisons or jails.

We didn't have a question about prisons or jails in the first version of the screener, but within a week we added it. I think it was important, since some prisons and jails have experienced huge outbreaks, and those are really hard to contain. (Today, we test asymptomatic people as capacity has expanded.)

How do you see the role of testing shifting moving forward?

Over the next 6 months, governors and public health officials are going to have to make some very careful choices balancing the economy versus the risk of new outbreaks. I think the data are going to be more valuable than ever for making those decisions.

Initially when the number of new cases was steeply rising, it was good to have data, but there wasn't as much that we would have done radically differently had the data varied slightly.  But as we get into a more stable place, we need to be able to use data to have a sense of how much of a better place we are in. How much are the rates of people testing positive coming down?

I think that there are going to be governors who really understand the importance of the data for making decisions in their state. I hope that the governors who really pay attention to the data have excellent outcomes that they can tout, so that they can say, “look: data worked, data helped.”

Before we go, what is one thing you hope readers can take away from this interview?

The biggest thing I'd like people to really understand is that social distancing isn't so much about protecting you personally, it's about population health and protecting the entire healthcare system.

Maybe you’re the kind of person who feels lucky and you think this isn't going to hit me so you don’t take precautions. You might get sick, and maybe you’re comfortable with that risk, but when you get sick you’re going to be on a bed in a hospital with a ventilator that somebody else needed.

This is so big that we don't have all of the hospital space we need, we don't have all the testing resources, we don't have all of the personal protective equipment for healthcare workers. When you get sick, it has this whole downstream effect on everybody.

This is a situation where it’s not about the individual, it's about our entire community and protecting everyone around us. Not just our families, not just the people we see in the grocery store, but protecting everybody.

I hope this can be one of those moments where people do things for the public good and not simply for themselves.

Posted by: Katherine Stein, Contributing Editor