The path from data to praxis.
I came up with this model when asked to give a talk to computer programmers and technologists at a technology conference in Seattle, WA around 2005.
The point was to explain that much more than technology is needed for human behavior change. I was making a pun on the communications protocol stack 
, in effect trying to extend it from technology into social psychology and political economy.
Leroy Hood came up with the idea of "P3" medicine--Predictive and Preventive plus Personalized. A friend of his suggested that a fourth "P" was needed--Participation. Thus the name P4 Medicine.
Dr. Hood, at the Institute for Systems Biology, involved me to help understand and realize the Participatory part.
At that time I was developing the patient inspired personal health record platform, the Shared Care Plan, along side Microsoft's HealthVault with Peter Neupert and Shawn Nolan. Nic Ivancic was the architect of the Shared Care Plan and Shawn Nolan was the architect of HealthVault, and together they made these two innovations interoperable. It was an exciting time filled with optimism.
The relationship between PeaceHealth and ISB lasted a couple of years until PeaceHealth, my then employer, changed strategic direction.
I appended the four Ps to the Human Stack to illustrate the part of the stack which require personal participation
While Leroy Hood's amazing technology and business acumen were the engine for the first two Ps (prediction and prevention) personalization had to reach beyond specimens and biological science toward people, social psychology, meaning making, and behavior change. This end of the spectrum may be less complicated but certainly more complex than the first two Ps.
Today I am still working on the top of the Human Stack, but now from nearer the person's home and less attached to the institutions of medicine and commercialized services.