Stanford’s First Entirely Digital Clinical Trial Overall a Success Although Possibly Overestimating Recruitment Targets


Stanford University School of Medicine reported on the first entirely digital clinical trial which disclosed the importance of the physical activity. The study depended on the use of a smartphone app. The study was designed to recruit 2,000,000 participants from 2015 to 2025. Four years in it would appear that the study hasn’t produced the numbers of participants expected but the results have shown tremendous promise as to the potential for 100% digital studies for certain studies.

The Study Background

The study sought to ask two questions including 1) Is it feasible to successfully run an entirely digital, randomized clinical trial? 2) Is it possible to encourage people to exercise more by using a smartphone app? The answer was yes to both.

The Study

Overseen by Euan Ashley, MBChB, DPhil, professor of medicine, genetics and biomedical data science at Stanford.

The MyHeart Counts Cardiovascular Health Study utilizes mobile health capabilities of smartphones and wearables to assess daily activity measures of the general population and compare these to measures of cardiovascular health risk factors and fitness. How people divide their time among exercise, sedentary behavior, and sleep all affect cardiovascular health, yet to date, these have largely gone unmeasured.

With the advancement of phone sensors and wearable fitness tracking devices these factors are now more straightforward to gather and measure. The use of smartphones by a large segment of the population allows for data collection of a un unprecedented scale. The investigators aim to amass activity and cardiovascular health data on thousands of participants as well as provide significantly more quantitative data on the type, duration, and intensity of daily activities.

In the second phase of the MyHeart Counts Cardiovascular Health Study (Randomized Assessment of Physical Activity Prompts In A Large Ambulatory Population) the researchers will conduct a randomized controlled clinical trial of four different physical activity prompts (intervention) and their effect on the level of physical activity in the study population as measured by change in step count.

Ongoing Results

The study used MyHeart Counts, an app that Ashley and other scientists at Stanford developed using technology support offered by Apple reports Stanford Medicine News. First deployed in 2015, the app was launched to track physical activity and other heart-related information, such as heart rate. It was the central tool for an end-to-end clinical trial including patient recruitment, consent, and interventions not to mention data collection from patients. 

The study opened up enrollment one year after the study start which was 2015. Over 18 months, 1075 participants have enrolled and completed at least one intervention and 493 have completed the entire trial. Their endpoint target was 2,000,000 participants according to, which they may not reach based on numbers shared thus far. The study ends in 2025.

Comment on Dropout Rates

In most studies, large dropout rates spell the end of the study. IN the digital world there is a low bar to entry. There is a low bar to exist as well. Studies can survive.

SmartPhone App Trials

It has been clear from the study results thus that smartphones are a powerful way to tap into the pervasive use and even dependence on this technology. Based on study results Ashley and the team saw about a 10% increase in activity compared to participants’ baselines. The results were detailed online Oct. 3 in The Lancet Digital Health. As mentioned TrialSite News reviewed the initial target of 2 million patients which seems the Stanford team hasn’t come close to achieving based on numbers thus far.

Lead Research/Investigator

Euan Ashley, MBChB, DPhil, professor of medicine, genetics and biomedical data science at Stanford.

Steven Hershman, Ph.D., director of Stanford’s mHealth in cardiovascular medicine

Anna Shcherbina, Graduate Student

Call to Action: Interested in learning more read the study results at Stanford Medicine News. TrialSite News will seek to invite the Stanford team to our TrialSite News Podcast Series.