The success or failure of health information systems is the result of a complex mix of people, organizational processes and technologies. I continually look for theories that help to explain the interaction between these dynamic elements.
I came across a paper presented at the 2002 International Conference on Systems Sciences titled Structuration Theory and Conception-Reality Gaps: Addressing Cause and Effect of Implementation Outcomes in Health Care Information Systems written by Angelina Kouroubali at the University of Cambridge in the UK. It applies the work of Anthony Giddens and Richard Heeks to a case study on the Isle of Crete.
Further Googling took me to the source paper for Heeks' work titled Why Health Care Information Systems Succeed or Fail. As is always the case, technology accounts for only one small part of eHealth success or failure. Heeks' model is based on the acronym ITPOSMO which stands for Information, Technology, Processes, Objectives and values, Staffing and skills, Management and structures, and Other resources: money and time. Heeks also developed a method for eHealth Project Risk Assessment called the Design-Reality Gap Technique.
These are three very good references. Download and read!