How representative are PatientsLikeMe patients to the general population?

Mimi Yin over at The Common Data Project blog posed some interesting questions about data in our communities:

Back in April, I wrote about the site PatientsLikeMe.com, which provides a wonderful new service that allows individual users to share the most intimate details of their medical conditions and treatments, which in turn creates a pool of invaluable information that is publicly available. However, I also wonder about how their data may be skewed because their users are limited to the pool of people who are comfortable sharing their HIV status and publicly charting their daily bowel movements. The question we have for PatientsLikeMe is: Who isn’t being represented in your data set? And how does that affect the relevance of your data to the average person who comes to your site looking for information? Who won’t find your data helpful because it’s not relevant to their personal situation?

First of all, Mimi brings up outstanding questions.  Let’s take the overall philosophy first, openness.  PatientsLikeMe is built around the idea that patients can drive their own health outcomes through sharing their health information.  This is a movement away from privacy as a paradigm for health management.  That being the case, the people who choose to be members have weighed the potential benefits and risks of sharing information and land on the benefits side.

PatientsLikeMe is certainly not for everyone.  As the early-adopters have been called the “vanguard” by Thomas Goetz in our recent New York Times Magazine article entitled Practicing Patients, these people are joining a movement to move the control of patient data back to the hands of patients and not the other stakeholders.  So it’s these people who have chosen to share their information with each other, with about 10% choosing to share with the world for everyone’s benefit.

The time is now for patients to take control and embrace this openness philosophy.

Now, to address those issues individually:

• How representative is our dataset? This varies by each community according to the size of our sample and the characteristics of the “typical patient” with that disease. For instance, our flagship ALS community contains over 1,400 registered patients, accounting for about 5% of the US population of 30,000 patients. Our community’s mean age at onset is 49 years old, relative to the population norm which is 54 years old, suggesting we get slightly younger users on the site; we also tend to have a higher proportion of longer survivors than one would find in the broader population. The larger the PatientsLikeMe community and the smaller the patient population, the more representative we are.

• How does that affect the average person who comes to your site looking for information? Not much! When you join PatientsLikeMe, we don’t show you the experience of the average patient. We show you the outcomes of a patient just like you. Through our advanced search feature you can find other patients who are similar to you demographically, geographically, or in terms of your illness profile.

• Who won’t find your data helpful because it’s not relevant to their personal situation? We believe that more data is always better; if that data is from someone who’s not quite like you, we show you the ways you differ. That way you can make your own adjustments and draw your own conclusions. At some point though it stops being about the availability of data and starts being about the ability of the user to act; our treatment database in HIV is of little use to someone without access to antiretroviral drugs. That said, the tools we provide can still help a patient through social support, sharing their outcomes with others who have been in the same position, and record their blood counts (if available).

Our favourite part of Mimi’s post states:

To state my case more strongly: Participating as a data point in data-driven research is a passive form of voting, the most basic of rights in a functioning democracy.

We’d even go one further and say that sharing important data about decisions you’ve made in order empower others is actually more important than casting your vote in a democracy; it’s more meaningful, you immediately gain experience and insight right back, and perhaps somewhat idealistically, it brings people together rather than driving them apart. Part of our mission is to make the case that sharing data works out better for everyone; the more people we convince, the more reliable our data will be, the better decisions people can make, the more people will be convinced to share their data…The movement begins….