Collaboration improves the quality of care: methodological challenges and evidence from US health care research.

At the present time when interprofessional collaboration in practice is reaching new levels of interest related to health care system changes in both the UK and the US, a key question being raised is: What are the outcomes and costs of interprofessional collaborative models of care? The purposes of this paper are to: (a) summarize past research efforts, primarily in the US, to examine whether interprofessional collaboration improves the outcomes of care, (b) articulate the continuing conceptual and methodological challenges associated with efforts to examine this relationship, (c) present more recent research in the US in which investigators have overcome some of the conceptual and methodological barriers to this type of research, and (d) identify gaps in knowledge and areas for future research on the relationship between collaborative models of care and care outcomes.