Whenever health professionals engage in practice, they make numerous clinical decisions. In making such decisions, the practitioner draws on a wide range of evidence. This will include knowledge of the basic biological and behavioral sciences, the health professional’s assessment of the current context and of the individual patient; their own experience; and their own current understandings of research reports they may have recently read. All of the knowledge that is used to make a clinical decision can be referred to as evidence – and the validity of this evidence may be variable.

When making decisions, clinicians (often quite subconsciously) are frequently trying to select an appropriate activity or intervention and to assess the degree to which the decision will meet the four practice interests of health professionals; i.e. the extent to which it is:

(Pearson, 2002)

Thus, evidence for practice takes many forms, and relates to these four practice interests of health practitioners. This is not well understood and in many countries, evidence in healthcare focuses largely on evidence of effectiveness. For example, the US allocated $1.1 Billion in
the 2009 federal budget to fund comparative effectiveness research (CER) programs. CER compares existing interventions (using a form of systematic review) to identify which is most effective. The Institute of Medicine defines CER as “the generation and synthesis of evidence that compares the benefits and harms of alternative methods to prevent, diagnose, treat, and monitor a clinical condition or to improve the delivery of care. The purpose of CER is to assist consumers, clinicians, purchasers, and policymakers to make informed decisions that will improve healthcare at both the individual and population levels” (Thill, 2010).

Central to CER are “pragmatic trials” – studies that measure effectiveness (Alexander & Stafford, 2009). Pearson (1998) has argued that, whilst evidence-based practice includes an interest in research directed to the establishment of effectiveness, it needs to go beyond this to include the qualitative domain. He says:

He goes on to suggest that “… evidence-based practice is not exclusively about effectiveness; it is about basing practice on the best available evidence.”

The diverse origins of problems in healthcare practice require a diversity of research methodologies. Thus, methodological approaches in this area need to be sufficiently eclectic to incorporate classical, medical and scientific designs along with the emerging qualitative and action oriented approaches from the humanities and the social and behavioral sciences. The development of inter-disciplinary research and a greater understanding of the relationship between medical, nursing and allied health interventions are also fundamental to the emergence of research methodologies which are relevant and sensitive to the health needs of consumers.