Single case study and evidence-based practice.

Single case study and evidence-based practice With the current emphasis upon evidence-based medicine in statutory health care provision in the UK, mental health nursing is challenged to justify its approaches. Psychological theories, once taken for granted in mental health nursing, are now being challenged by new definitions of evidence. In this paper the authors focus upon the use of individual case study. The discussion questions the validity of applying the hierarchies of evidence proposed by evidence-based medicine to mental health nursing theory and practice. The role of case study as the prime source of evidence is argued and is justified in mental health nursing research and practice.