Trisha Greenhalgh opened the 1st Realist Evaluation and Synthesis conference in Liverpool last week with the question Should we align realist methodology and evidence-based medicine? She surveyed the audience to reveal a lot of uncertainty.
She referred to the RealEBM debate and her recent BMJ article which posed the question Evidence-Based Medicine: A movement in crisis to substantiate the crisis of confidence. She discussed the critical perceptions of EBM; that randomised controlled trials (RCTs) are the gold standard for evidence, yet they don’t help clinicians make individual decisions and they can be used for political and financial purposes.
I was not able to respond in person at the time; but have summarised my response…
Many experienced clinicians approach us at the Centre for Evidence-Based Medicine in Oxford to learn about ways to improve their understanding and use of research evidence in clinical practice. As they learn about the 5 steps of evidence-based practice they quickly realise that, as they ask important clinical questions and search the many databases, they need to engage with research more broadly than just interpreting RCTs. They also realise that many clinical questions are in fact complex questions that cannot be answered by RCTs alone. A good RCT can only tell you about the effect of an intervention – it cannot tell you why the interventions was successful or whether it can be implemented in another environment. To answer these questions we need alternative methodologies. Qualitative, mixed and realist methodologies could potentially help to provide answers to the more challenging and important clinical questions.
Therefore it is vital for the EBM community to continue to help clinicians answer the real questions posed by patients and the complexity of clinical practice. As clinicians have learned about EBM, they have answered some of the more straightforward clinical questions, leaving the complex ones unanswered! We still need to recognise the importance of asking a clear question; and use this to guide the best study design to search for. It is becoming obvious for many clinicians that there is a need to engage in alternative methodologies to the gold standard RCT. Therefore we need to build up a repertoire of different study designs to keep up to speed with the clinical questions that are being asked. To do this, we need to understand both the practical steps of different methodologies, and we need to critically evaluate their comparative quality and rigor.
It is in determining research rigor, that there are significant challenge across methodologies. The positivist epistemology of quantitative research requires critical appraisal of the risk of bias, through detailed checklists of internal and external validity. In contrast, constructivist qualitative researchers emphasise concepts such as credibility and trustworthiness. While there has been a long debate about the fundamental differences between qualitative and quantitative research, there is an increasing pragmatic awareness of the need to mix these methods to answer contemporary research questions. Later in her talk, Trisha indicated that Realism may be a philosophical mid point on a continuum between positivist and constructivist paradigms. Realists focus on making sense of social realities by developing explanatory theories to explain the impact of certain situations on the outcomes of research interventions. In fact, realist reviewers aim to answer the important question of what works, for whom, in what circumstances. Therefore, it seems that the realist paradigm and methodologies will be very important in helping clinicians to answer complex questions now, and into the future. The EBM community needs to engage!