AIMS:To examine issues around the use of mixed methods research in doctoral research in nursing and healthcare. We raise questions around challenges and appropriateness of this type of research methodology for doctoral students. BACKGROUND:In recent years, mixed methods research has grown rapidly in health-related research. As an emerging research methodology, mixed methods research has much to offer doctoral researchers in health care who increasingly are faced with complex research issues. However, despite evolving as a research paradigm, researchers from both qualitative and quantitative perspectives have hotly debated application of mixed methods approaches. The body of supporting knowledge underpinning mixed methods research continues to grow and become refined. Evolving complexities pose new challenges for newly-enrolled doctoral students. DESIGN:Discussion paper. METHOD:Using a discursive approach, we raise questions around the challenges and appropriateness of this type of research methodology for doctoral students. RESULTS:Mixed methods research poses a unique range of methodological challenges that need to be carefully considered by research students when choosing their research methodology. These include scope of methodological learning required, additional time for data collection and analysis, need to acquire additional skill sets, approaches to reporting study results, dissemination of findings and specific supervisory support and thesis examination issues. CONCLUSIONS:Mixed methods approaches can make important contributions to clinical research. However, their application to doctoral studies is challenging and should only be considered where appropriate to answer the research question. RELEVANCE TO CLINICAL PRACTICE:Mixed methods research approaches are commonly used in doctoral studies undertaken to understand clinical nursing practice and can make an important contribution to knowledge. However, there is a need for appropriate application of the methodology to ensure strong, appropriate research outcomes.