Between 1996 and 2002, Jo Phelan, PhD, and Bruce Link, PhD, sociologists and epidemiologists at Columbia University, elaborated and tested their theory that certain social conditions, such as socioeconomic status, may be "fundamental causes" of diseases.
The project was part of the Robert Wood Johnson Foundation's (RWJF) Investigator Awards in Health Policy Research program.
Phelan and Link published the following findings in a series of articles:
- The absolute level of material resources and access to key social and economic resources affect health.
- People with higher income and education levels derive greater benefit from advances in health care.
- The relationship between socioeconomic status and mortality is much stronger for highly preventable diseases.
- Low-income people in states where income inequality was high were more likely to have some risk factors than their counterparts in states with less inequality.
- Humanity's ability to control disease has improved health over time, but Phelan and Link argue that improvement is distributed in a system of socioeconomic inequality.