The kind of models we should be talking about

Rational thinking and logical deduction are essential life skills that facilitate understanding, purpose, and happiness in lived human experience. They are fundamental skills required for health professionals to make reasonable, ethical and informed decisions. Yet many health and medical professionals still fail to grasp the most basic physiological truth of the human experience, thereby violating the primary ethical ethos of do no harm on a daily basis.  What is this truth?

The simple fact that humans are a complex system that is uniquely shaped by each of their own individual experiences, and that all the systems of the human body are interlinked. While often taught in isolation for simplicity, and given the complexity of being human, the medical and health system continues to fragment the body through medical specialisation. You could easily be forgiven for thinking that people exist as whole people when you have to go see separate professionals for almost every region of the body you can think of. I do think specialisation improves patient care and is necessary. However, the system's failure lies in the absence of a guiding central philosophy for understanding the human experience. Most of medicine for a long time primarily operated within a biomedical model with the general assumption that something happens to the body, the body sends information to the brain telling it what is going on and what a person experiences should be relatively consistent between people and directly related to whatever physical event has happened to or inside the body. Anyone who has been alive for a little while and has been paying attention can tell you they have rarely ever had an experience that supports or justifies such a simplistic reduction of a human experience. The list of examples is endless as to why a model focused solely on physical inputs that equate to an objective, unified, experientially accessible truth is grossly flawed. However, it is clear to see where it comes from as well. Much of medicine and health care is based on clinical pattern recognition: the general practice of clustering subjectively reported symptoms with objective test results to arrive at a diagnosis, because signs and symptoms can be clustered, and it works. Yet, holistic healthcare is not solely about treating a diagnosis; it is about treating the whole person. This is where the shortcomings of a biomedical model of care and practice become so clear.

Biomedical

Figure 1 presents a basic representation of the biomedical model, with the most traditional version depicting a unidirectional relationship in which a biological reaction in the body dictates lived experience. Within the traditional biomedical model, psychological factors are usually acknowledged, but rather than being regarded as factors that can affect biology or experience, they are treated as a separate branch of medicine.  You fundamentally have a biological or a psychological issue with the person's social context, and their individual experience is dictated by one or the other, rather than by interaction between factors or by the experience itself having any impact on either.

Figure 1. Biomedical Model

Bio-psycho-social

Before moving on to discuss the biopsychosocial model, it is worth pausing to consider what is sometimes described as the bio-psycho-social model. Some may argue that these are the same; however, I do not believe they are. I believe that the bio-psycho-social model is utilised when the biopsychosocial model is only partially understood; therefore, by extension, human physiology, psychology, biomechanics, social behaviour, etc., are only partially understood. Within the bio-psycho-social model, the individual spheres of influence (the bio, psycho, and social elements) are typically viewed as separate, but it is recognised that they can influence experience. Progressions of this model extend to the point where people recognise that a person's experience can influence any or all spheres, and that biology can drive psychology, or vice versa. As understanding progresses, individuals reach a point at which they can experience their own lives with greater depth and perform their roles professionally with greater competence.

Figure 2. Bio-Psycho-Social Model

Biopsychosocial

The biopsychosocial model recognises that unidirectional connections between experience and physiology do not exist. While it may appear more complex, it is in fact the simpler model because it offers greater depth and scope for explaining an individual’s experience. As a model, it may still fail to capture all the factors that can impact a person’s experience, but the core notion that someone’s experiences, social context, their biological state and their own psychology will all influence what they experience as an output from the brain from any given input is a fundamental concept for the provision of ethical patient care. This is also why, for many primary contact practitioners within the health and medical system, utilisation of a biopsychosocial model is essential.

A common misconception in discussions of differences between the biopsychosocial and biomedical models is the belief that biomedical knowledge exists outside the biopsychosocial model. This, however, is an error in logic, as the biopsychosocial model utilises all the biomedical knowledge of the biomedical model, along with knowledge from the social sciences, immunology, biomechanics, physiology, psychology, etc., to create a framework in which biomedical knowledge can be utilised more comprehensively to provide patient care. Discussions around separating biomedical thinking or skills from a biomedical model suggest a gross misunderstanding of what the biopsychosocial model is and a thoroughly reductionist view on what it means to be human.

Figure 3. Biopsychosocial Model

Simply utilising a biopsychosocial model for both the provision of health care and the description of the human experience does not guarantee ethical and appropriate care. It undoubtedly serves patients, clinicians, and health care systems better and provides a reasonable framework for protecting patients from harm that often occurs within a purely biomedical model. Nevertheless, it would be unreasonable throw the baby out with the bathwater as it were. Not all practitioners should be concerned with mastering biopsychosocial care. Trauma and Orthopedic surgeons, for example, operate primarily in a purely biomedical world once the patient is on the table, and being experts at their craft does not necessarily require them to possess the skills to be holistic practitioners. It is a much more important skill for primary care and front-line practitioners.

The benefits and simplicity of the biopsychosocial model make it easy to integrate and teach.

• For example, one patient gets knee pain when they squat but knows that there is nothing structurally wrong with their knee, knows how to modify the movement to ease their pain and can perform self-treatment of their own impairments to enable them to continue participation in their activity without restriction. When that fails, they have been taught to modify their activity participation and select different exercises for a short period before returning to squatting, and that, if their normal strategies are not working, they have someone they know and trust to whom they can go for help.

• A second patient starts getting knee pain when squatting, and is worried that they have done some kind of structural damage to their knee, so they take time off from the activity. They had a friend tell them about when they had a similar pain; they went to their doctor and were told they had torn something and needed surgery. The surgery led to time off from work that the person can’t afford, so they simply stop the specific activity and avoid doing things that cause any similar kind of pain.

Here, patient one has healthy pain beliefs, understanding that hurt does not equal harm. They have been educated and empowered to actively participate in their own care and to seek help when needed, and they are in a positive social environment where they know they can obtain assistance.

Alternatively, patient two has had no de-threatening input to explain how they should interpret the information they have received from their body, requesting a change, so they are unsure how to respond to the painful experience. From a social context, they have been provided information that has increased the potential threat perception of the pain they have experienced, leading to a psychological response of overprotection and withdrawal from activity and participation. Withdrawal from participation can lead to biological changes, such as tissue deconditioning, which further reduces tissue tolerance capacity and, consequently, protection against pain perception, likely resulting in less favourable outcomes.