Why might systems thinking in medicine be important?

I started this blog largely because I became fascinated by systems, particularly complex adaptive systems, and the potential of systems science and systems thinking to transform the way we conceive of, practice, and learn medicine. The word system is one I have been familiar with in medicine from the moment I entered medical school - we encounter systems explicitly in many areas, but particularly when learning about body systems: the cardiovascular system, the endocrine system, the nervous system, and so on. This seems partly a by-product of the way medicine has been taught in traditional and systems-based curricula, but also a result of the way medicine is practiced in secondary care (i.e. in hospitals) in most parts of the world, with departments often classified by the system they specialise in.

So what is different for me now? Why have I become so taken with systems ideas? I think it is the surprising power of this way of approaching medicine in revealing hidden patterns; the deep linkage it makes between seemingly disparate phenomena; and the way the ideas in systems science cross disciplinary boundaries and provide a unifying set of principles by which we can better understand our patients, their illnesses, and our healthcare system. This way of thinking has transformed the way I approach my practice as an educator and a physician, and I think it has improved what I do. A grand statement for sure - I hope you will see some of the rationale for this as you explore my musings and reflections.

Perhaps we should start by asking what we mean when we talk about a "system", and why "thinking in systems" might be helpful in medicine. The first question can be quite difficult to answer, and there are many definitions if you look for them, but to my (rather simple) mind and not wishing to overcomplicate things, a system is "a group of inter-related parts that interact with one another to produce a function or behaviour". When we talk about systems thinking, things can get more complicated, and there are a couple of helpful videos that introduce this below. The first is from the Centre for Disease Control in the USA, which helps us see its use in healthcare:

From: https://youtu.be/Fo3ndxVOZEo

Importantly, as the video explains, our mental models influence our approach to a problem. Systems thinking can help us by framing problems appropriately, widening our perspectives, appreciating dynamics, and continually improving our understanding of the system we are considering. But how do we educate our students to think like this? The next, a talk by Dr Derek Cabrera, discusses thinking skills, and proposes that systems thinking can be simplified using his 4-part framework of Distinctions, Systems, Relationships and Perspectives (DSRP) which is nice and memorable. I'll discuss this further in future posts.

From: https://www.youtube.com/watch?v=dUqRTWCdXt4

We see similar issues as Dr Cabrera describes in medical students. There are increasing moves to address this within medical education, but I'm not sure we have it right in our curricula yet. One problem is that we humans tend to think in a linear fashion, such as cause and effect chains, and often don't appreciate the wide and interconnected nature of many of the phenomena that we are dealing with, or indeed the dynamic nature of systems, including realising that feedback loops are in operation as the CDC video discusses. A systems approach helps us to conceptualise in a way that helps us to see relationships, appreciate dynamics, and gain perspectives, that we might otherwise have missed. It can help us appreciate level hierarchies, such as phenomena occurring at the biochemical, cellular, tissue, organ, body system and whole body level, right up to the social, organisational, national and global political levels. This is important - phenomena at these various levels can interact in myriad ways; appreciating the relatedness of these phenomena can, I think, help us better understand patients, their illnesses and the environment in which they live, and I think that teaching our students these skills will make them better doctors.