Theories and models

The importance of theory and models, which are theories made more concrete, must be stressed. Rehabilitation has suffered from the dominance of the biomedical model of illness since rehabilitation emerged in 1918. The advent of a better theory of illness, the biopsychosocial model, has yet to impact most healthcare significantly, excluding rehabilitation. I have written and spoken about models of illness for most of my professional life. This interest inevitably led me to consider how we use words to capture essential concepts, including the meaning of rehabilitation. Many pages and posts on the Rehabilitation Matters website concern linguistic and philosophical concerns about the words and concepts we use.

Introduction

In 1998, Priscilla Alderson stressed that theories are crucial: “… theories are at the heart of practice, planning, and research. All thinking involves theories …” and she went on to say, “… when theories are implicit, their power to clarify or to confuse, and to reveal or obscure new insights, can work unnoticed.” Rehabilitation has been weak in developing and using a robust theoretical basis for its work, and it currently has no explicit theory.

The absence of a strong, conceptually sound and, preferably, evidence-based set of theories covering rehabilitation’s clinical work has had significant adverse consequences, such as:

A lower status when competing against most biologically-based clinical specialities for resources,
A lower likelihood of receiving research funding and support,
There is a lack of understanding of rehabilitation among most healthcare workers,
The speciality has various views about what we do and our purpose.

Theories and models.

Rehabilitation took up the biopsychosocial model of illness immediately after its publication, most notably using it as the organising principle of the World Health Organisation’s classification of the consequences of disease, a system they improved in 2000 to the International Classification of Functioning, Disability and Health (ICF). This improvement was primarily driven by patients and people with disabilities, supported by rehabilitation academics.

However, the rehabilitation clinical community made little use of the model to advance their practice or the understanding of rehabilitation by the wider healthcare community. The model was used in research and was discussed more generally. On the other hand, the theory’s practical consequences and implications still need to be developed. This website has numerous pages on the biopsychosocial model of illness, integrating it into practice and highlighting some of its consequences, such as the imperative to perform a person-centred assessment.

Broadening our perspective.

Rehabilitation is holistic. Therefore, it inevitably will interface with multiple academic disciplines. Most of these disciplines will have theories. For example, the psychological theory of motivation developed by Maslow, the goal-setting theories developed in business studies by Locke and Latham, and the learning theories used in psychology and education all have much to teach rehabilitation. Indeed, the originator of the biopsychosocial model of illness, George Engel, was a psychiatrist. He doubtless drew on work by sociologists and psychologists, among other disciplines.

We could use many theories to develop a sound intellectual basis for rehabilitation. Measurement theories are used, especially Rasch analysis, though the added value of this technique is still to be determined. Complexity theories can surely help us; Rachel Stockley and Ian Graham have argued for embracing complexity in rehabilitation, but I have not seen much published in rehabilitation journals.

Ideally, an academic department with appropriate resources will take up the challenge. It could develop links with various other disciplines, selecting and adapting theories that could better inform our clinical practice.

The posts

In the meantime, the posts in this category will cover any theory or model that might improve rehabilitation. The most recent eight posts are below; more can be loaded using the button at the end.

What is a diagnosis? Part 2

First published: November 24, 2025 Last updated: November 23, 2025 In What is a diagnosis? Part 1, I explained that diagnoses can generally be divided into biomedical diagnoses supported...

Biopsychosocial disequilibrium

First published: November 14, 2025 Last updated: November 14, 2025 How can we tell when something is wrong with us? In a popular post (6,800 views over four years),...

Malady

First published: November 6, 2025 Last updated: November 6, 2025 In January 1781, The London Medical Journal published a 19-page review of a book written by Dr Tiffot, a...

Basic Biopsychosocial Framework.

First published: October 3, 2025 Last updated: 3 October 2025 This post explains the framework used in the biopsychosocial model. While the framework is a powerful analytical tool, a...

Biopsychosocial healthcare

First published: September 25, 2025 Last updated: 25 September 2025 The medical model and biomedical healthcare are two of many terms used to describe the traditional and culturally dominant...

What is a diagnosis? Part 1

First published: April 6, 2024 Last updated: November 23, 2025 In healthcare, a diagnosis is a label assigned to a health condition. The Oxford English Dictionary defines diagnosis as:...

Personal factors in rehabilitation

First published: October 21, 2023 Last updated: March 22, 2025 Personal factors (WHO ICF) are an invalid construct. They cannot exist separate from the person as independent influential factors....

Healthcare theory

First published: October 16, 2023 Last updated: October 17, 2025 What theory underlies the delivery of healthcare? The design of hospitals, services, policies, and almost every other aspect of...