In a snowy café-restaurant Polder at Science Park Amsterdam patients, researchers, policy-makers, IT specialists and care providers came together. The common denominator: scaling up self tracked health data for the common good. Gary Wolf, inventor of the term Quantified Self, was present as well.

The active Quatified Self community consist of about 10.000 people. A 'small fire' Gary calls it. Each member has their own reason for tracking themselves. Most of the stories are about people learning from their own health data and managing their own illness. People with similar conditions share their  experiences in an attempt to better understand and improve their situation. But how could the insights of a single person, be translated to meaningful insight for the larger group? Wat is the relationship between self-tracking and the common good? These questions were central to the workshop 'Sharing self tracked health data for the common good', during the national eHealth week 2019.

Martijn de Groot, co-founder of the Quantified Self Institute in the Netherlands, explains what the Quantified Self community is about: What did you do? How did you do it? And what did you learn from it? Sharing the insights and the method of collecting data is what makes the difference. Quantified Self is often strongly related to wearable tech, like fitbits and smartwatches. However, collecting data can be done in a low-tech way as well: by standing on a scale and writing down the changes over time for example. The real 'self-trackers' share those findings and how they got them.

Outside of self-tracking an increasing amount of people look to the internet for information about health issues. Of all the EU countries, the Netherlands is leading in 'most searches for health related topics'. On the one hand it is positive that people are actively informing themselves about health issues. However, it can also lead to scepsis towards medical professionals. People can feel like they are not being taken serious if the conclusion of a doctor differs from their own findings.


Classical medical research mainly focusses on the 'randomized controlled trial' (RCT) to determine whether a treatment is effective . Generalized conclusions are drawn, that don't always fit the individual situation. At the same time, a treament that works for one person, doesn't always work for the larger group. How can these two worlds come closer?

An example of self tracked health data being helpful for a patient, is Sara Riggare, a Swedish woman with Parkinson. Ze visits her doctor for half a hour two times per year and spends the remaining 8765 hours in self-care. She monitors whether her situation improves or not after a change in patterns. Be that adjustments to medication or a change in her workout schedule. She collects both quantitative measurements as notes about how she is feeling. She shares this data with her doctor, who in turn can adjust treament as needed.

Much is needed to come to a result like that: the right instruments, support, domain knowledge and systemic recognition. For a person like Sara it is achievable to do this largly on her own. She is highly educated and is capable of recognising patterns in data. She has the support of her doctor and the equipment needed to do the measurements. This is hardly a 'standard' situation or one that is easy to reach. Let alone acquiring domain knowledge, especially with access to scientific papers being limited.

This led to many questions arising during the discussion about how self-tracking: When does data become proof? How do you make sure that people contribute their data? How can you ensure people use the same method of measurement? What is the level of commonality; de condition, the method, the symptoms? Hoe can you prevent people from providing fake data? How do you ensure privacy is a system like this? On top of that, it seems systemic change is necessary in health and its governing processes. At the moment, efficiency and profit are considered more important than value. All not easy questions to answer.

That Quanitified Self can contribute to individual care is evident for examples like Sara. But to what extent it can contribute to medical science is unclear at the moment. Despite the challenges, Gary remains positive. He sees the fire of the Quantified Self movement burning and even calls to article 27 of the Universal Declaration of Human Right: 'Everyone has the right freely to participate [..] and to share in scientific advancement and its benefits.'

This workshop was part of the kick-off of the 'Co-coperatice Citizen Science in Health' series of the Mijn Data Onze Gezondheid foundation.