Chapter 1 –Definitions and concepts of PRM

European PRM Bodies Alliance

For this paper, the collective authorship name of European PRM Bodies Alliance includes:

European Academy of Rehabilitation Medicine (EARM),
European Society of Physical and Rehabilitation Medicine (ESPRM),
European Union of Medical Specialists PRM section (UEMS-PRM section)
European Union of Medical Specialists PRM Board (UEMS-PRM Board)
The Editors of the 3rd edition of the White Book of Physical and Rehabilitation Medicine in Europe: Pedro Cantista, Maria Gabriella Ceravolo, Nicolas Christodoulou, Alain Delarque, Christoph Gutenbrunner, Carlotte Kiekens, Sasa Moslavac, Enrique Varela-Donoso, Anthony Ward, Mauro Zampolini, Stefano Negrini
The contributors: Pedro Cantista, Gerold Stucki, Jerome Bickenbach, Christoph Gutenbrunner Camelo, Carlotte Kiekens, Juan Carlos Miangollara, Daiana Popa, Sampaio, Pedro Soares Branco

Abstract

In the context of the White Book of Physical and Rehabilitation Medicine (PRM) in Europe, this paper deals with the definitions and concepts relevant for PRM. Physical and Rehabilitation Medicine is the primary medical specialty responsible for the prevention, medical diagnosis, treatment and rehabilitation management of persons of all ages with disabling health conditions and their co-morbidities, specifically addressing their impairments and activity limitations in order to facilitate their physical and cognitive functioning (including behaviour), participation (including quality of life) and modifying personal and environmental factors.

To arrive to this PRM definition we need to consider a conceptual description of it. Several fundamental aspects must be observed namely functioning, disability and rehabilitation.

These definitions are include and presented in this chapter:

Functioning: all that human bodies do and the actions that people perform. In the International Classification of Functioning, Disability and Health (ICF), functioning is operationalised in terms of functioning domains, and these domains are partitioned into the dimensions of Body Functions and Structures, Activities and Participation;
Disability: the problem a person has performing the actions that he or she needs and wants to do, because of how an underlying health condition – a disease, injury or even ageing – affects his or her performance in his or her actual environment;
Rehabilitation: a set of measures that assist individuals, who experience or are likely to experience disability, to achieve and maintain optimum functioning in interaction with their environments

The ICF definition of disability clearly distinguishes between problems that result entirely from the underlying health condition (capacity) from problems arising from the interaction between capacity and the environment and personal factors (performance).

This paper approaches all these concepts that are essential to the understanding of the PRM strategy to evaluate disability and implement interventions that may lead to the improvement of functioning and health.

Key words

Physical and Rehabilitation Medicine, Europe, Disability, Functioning, Rehabilitation

Introduction

The White Book (WB) of Physical and Rehabilitation Medicine (PRM) in Europe is produced by the 4 European PRM Bodies and constitutes the reference book for PRM physicians in Europe. It has multiple values, including to provide a unifying framework for the European Countries, to inform decision-makers at the European and national level, to offer educational material for PRM trainees and physicians and information about PRM to the medical community, other rehabilitation professionals and the public. The WB states the importance of PRM, that is a primary medical specialty. The contents include definitions and concepts of PRM, why individuals and society need reh, the fundamentals of PRM, history of PRM specialty, structure and activities of PRM organizations in Europe, knowledge and skills of PRM physicians, the clinical field of competence of PRM, the place of PRM specialty in the healthcare system and society, education and continuous professional development of PRM physicians, specificities and challenges of science and research in PRM and challenges and perspectives for the future of PRM.

PRM is a primary medical specialty responsible for the prevention, medical diagnosis, treatment and rehabilitation management of persons of all ages with disabling health conditions and their co-morbidities, specifically addressing their impairments and activity limitations in order to facilitate their physical and cognitive functioning (including behaviour), participation (including quality of life) and modifying personal and environmental factors.

To arrive to this PRM definition we need to consider a conceptual description of it. Several fundamental aspects must be observed namely functioning, disability and rehabilitation.

The concept of functioning deserved the World Health Organization (WHO) attention since many years in several circumstances. It inclusively became the basis of a Health Model and the object of one of the main WHO classifications – The International Classification of Functioning, Disability and Health (ICF). (1)

We may say that functioning is a WHO’s major concern and through the ICF Model WHO achieved an operationalization of Health.

PRM is considered the Medical Specialty of Functioning and logically ICF became its main reference as conceptual model, tool and taxonomy. Although the physical aspects of this specialty remain, its previous content of two separate parts (“physical interventions” and “rehabilitation”) evolved into an integrated model inspired by the ICF developments.

Disability is an umbrella term, covering impairments, activity limitations and participation restrictions. An impairment is a problem in body function or structure; an activity limitation is a difficulty encountered by an individual in executing a task or action; while a participation restriction is a problem experienced by an individual in involvement in life situations.

Disability is thus a complex phenomenon, reflecting the interaction between features of a person’s body and features of the society in which he or she lives. Overcoming the difficulties faced by people with disabilities requires interventions to remove environmental and social barriers

According to the World Report on Disability, rehabilitation is “a set of measures that assist individuals who experience, or are likely to experience, disability to achieve and maintain optimal functioning in interaction with their environments” (World Health Organization, 2011).

Rehabilitation in general and PRM in particular seek to optimize functioning in all domains and attempt to eliminate or ameliorate, the experience of disability.

But to define PRM as a single medical specialty we should take into account its professional, scientific and methodological identity.

This chapter brought us a PRM definition in Europe which is based on the same concepts that influenced WHO establishment of the ICF but also takes in consideration its biomedical nature.

Functioning

Functioning, WHO’s health information reference

Since its foundation in 1948, WHO’s mandate has been to achieve “the enjoyment of the highest attainable standard of health as a fundamental right of every human being” in which health is defined as the “…state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.”(1)

To monitor this aspiration, WHO has regularly updated the International Classification of Diseases (ICD) as a universal reference system for recording mortality and morbidity (2). Its latest version, the ICD 11, will also allow for the description of both the biomedical character and the impact of health conditions. (3)

In 2001, the World Health Assembly endorsed the International Classification of Functioning, Disability and Health (ICF) (4) in order to operationalize both the biomedical nature of health conditions – body functions and structures, and their impairments – and the overall impact on the lived experience of health in interaction with the person’s environment. The ICF provides a classification and a standard international common language in terms of which the lived experience of health can be operationalized at the individual and population levels. In the ICF, the biomedical nature and the overall impact of health conditions, in the context of people’s lives, taking into account the environment in which they live and their personal factors, is called functioning.

The ICF is an international classification of health and functioning; it is also an information reference system for the standardized description of health, functioning and disability at all levels of health and related systems, including the social, education and labour ones. The ICF is meaningful and useful to practitioners who aim to optimize functioning of individual patients, policy makers who aim to shape the health system in response to people’s functioning needs and requirements, and researchers who aim to explain and influence functioning as well as the sciences and professions of functioning.(5)

Functioning, WHO’s Operationalisation of Health

‘Functioning’ is the central concept of the ICF and denotes the complete set of human body functions and structures, as well as all human actions, simple and complex (Figure 1).

In brief, functioning is all that human bodies do and the actions that people perform. In the ICF, functioning is operationalized in terms of functioning domains, and these domains are partitioned into the dimensions of Body Functions and Structures, Activities and Participation. These are further organized in terms of a spectrum from simple to complex, from a basic body function such as seeing to highly complex and socially-determined areas of participation such as working or participating in community life. As a classification, the ICF is designed to be comprehensive, yet flexible, providing the clinician or researcher with a complete language of functioning while allowing for expansion through the specification of additional domains if needed.

Each of the ICF functioning domains is conceived as a continuum, from total absence of functioning to full functioning. At a point in time, everyone’s level of functioning in every domain can, in principle, be described and, depending on the intended research or clinical purpose of doing so, a slice-in-time comprehensive portrait of a person’s overall functioning can be also described. Moreover, as a person’s overall functioning will vary on a continuum over a lifetime, the ICF provides a reference language for longitudinal description as well. While functioning increases during a person’s early years, it will decrease in consequence of injuries and diseases and ultimately with ageing. With sufficient population data, it is therefore possible to construct representative trajectories of ageing, in light of the occurrence of specific health conditions and comorbidities, in terms of which the potential impact on functioning of clinical and population interventions can be described or predicted.

Practical tools to Implement the ICF in Clinical Practice, Service Provision and Payment, Policy and Research

Practical tools facilitate the ICF application – a clinical data collection tool and an ICF-based reporting tool (5,6) – for a wide range of purposes. ICF is a classification, so in order to use it we need a variety of tools that move the classification into practice. These tools allow us to specify which domains of functioning we wish to document; make it possible to collect data on functioning consistently, at the clinical or population level; and make it possible to report the data collected using a common metric, which allows for the valid comparison of functioning data collected from various sources (Figure 2). Accordingly, in clinical data collection planning, for a research study or for reporting already collected data, ICF users need to ask themselves the following four questions about functioning (7,8):

What ICF domains do we want to document? (E.g. by using the ICF Generic Set, the ICF Rehabilitation Set or an ICF Core Set for a specific health condition, along the continuum of care, or a context such as vocational rehabilitation). (9–12)
What perspective do we wish to take (i.e. either capacity or performance)?
What data collection tools will apply to our purpose?
What metric approach do we wish to use for reporting?

The ICF and Functioning in Rehabilitation

The ICF is fundamental to rehabilitation, the fourth health strategy along with curative, supportive and preventive ones.(13,14) The ICF is also fundamental to the field of PRM, which indeed might be called the medicine of functioning.(5,13,14) This is because the overall objective of both rehabilitation and PRM is to optimize a person’s functioning and thereby increase his or her quality of life.(15) PRM achieves this by optimizing through treatment the intrinsic health aspects of functioning, or ‘capacity’ in ICF terms, or by means of enabling changes to his or her environment to optimize the person’s actual performance of functioning. These interventions are only successful when they are directed to the interaction between health condition and environmental factors, as only then interventions can optimize the overall outcome of functioning. Ultimately, PRM’s goal is to translate a person’s intrinsic capacity or biological health into actual performance in interaction with the environment and personal factors, that is, the person’s lived health. In brief for rehabilitation in general and PRM in particular, functioning is the starting point of clinical assessment, the anticipated outcome of intervention, and the basis for quality management of interventions.

To describe, understand and influence functioning, PRM must rely on the ICF, both in terms of its underlying conceptual model of functioning and, more practically, on its classifications that can be used to ensure comparability of collected and reported data. The ICF can be applied in the description of individual patients (16) (Table I) as well as populations (Figure 2). With the ICF, intervention targets and goals can be specified in terms of the person’s functioning level (across relevant domains), the underlying health condition and comorbidities, and the relevant personal and environmental factors that shape the person’s lived experience of health. Interventions themselves can be specified using the International Classification of Health Interventions (ICHI) that classifies functioning, surgical and pharmacological interventions. The joint use of the ICF, the ICD and ICHI thereby allows for a comprehensive standardized coding of the full rehabilitation cycle, including assessment, assignment, intervention and evaluation. (17)

In order to foster the implementation of the ICF in day-to-day rehabilitation practice, the UEMS-PRM section and Board is leading a European effort towards a system-wide implementation of the ICF in PRM, rehabilitation and health care at large in interaction with governments, non-governmental actors and the private sector. The effort is aligned with the International Society of Physical and Rehabilitation Medicine (ISPRM)’s work-plan with WHO. (18,19)

Disability

Disability and WHO’s ICF

The International Classification of Functioning, Disability and Health (ICF) (4) captures our intuitive notion of a disability as a problem a person has performing the actions he or she needs and wants to do because of how a underlying health conditions – a disease, injury or even ageing – affects his or her performance in the person’s actual environment. In the ICF, this experience is conceptualized in terms of the basic ICF notion of functioning across domains of body functions and structure, activities and participation – i.e. everything the body does and the actions, simple and complex that people perform – in interaction with environmental factors that can act either as barriers (limiting performance) or facilitators (enhancing performance). Thanks to the ICF this potentially complex experience is operationalized by a classification, so that the experience can be accurately and fully described, in an internationally standard language.

The ICF definition of disability is somewhat broader than our everyday notion since it includes impairments (problems in body functions and structures) and clearly distinguishes between problems that result entirely from the underlying health condition (capacity) from problems arising from the interaction between capacity and the environment and personal factors (performance). Since rehabilitation in general and PRM in particular seek to optimize functioning in all domains, it can be said that these health strategies address, and attempt to eliminate or ameliorate, the experience of disability.

Disability epidemiology

For decades the challenge has been to reach a consensus about the definition of disability as a first step toward a true epidemiology of disability. Although the ICF has now established a consensus conceptualization, the current state of the epidemiology of disability tends to confuse two experiences: problems people experience performing actions entirely because of their state of health – the capacity perspective – and problems people experience resulting from the interaction between their state of health and environmental and personal factors – the performance perspective. Although they differ, both perspectives are important to estimate the prevalence of disability as well as to understand rehabilitation practice. (7,20) In line with its Disability Action Plan,(21) WHO has taken the step to refine disability epidemiology by developing a Model Disability Survey that clearly distinguishes the capacity from the performance perspectives, in order to disentangle the health from the environmental determinants of the experience of disability.(22)

Disability interventions

From the performance perspective – i.e. the actual lived experience of disability – limitations in the capacity to perform in some domain such as in mobility or major life activities may be considerably reduced by appropriate assistive devices and other environmental facilitators that enhance performance and so reduce disability. Yet these rehabilitation interventions require us to be able to translate the potential gains from capacity improvement and environmental changes on the actual performance of actions. As a matter of rehabilitation practice, the ICF makes it clear that these interventions must focus on the interaction between person and environment. The effectiveness and quality of rehabilitation interventions must be assessed, not merely in the extent of capacity improvement or environmental facilitation, but in the actual outcome of this interaction. That is what it means to optimize functioning.

Disability evaluation

Since domains of functioning lie on a continuum from no problem to complete problem, disability is not the opposite of functioning, but rather a range of functioning within the overall continuum that, intuitively, lies toward the complete problem end of that continuum. There is therefore no single point on the continuum where, for every domain, functioning ends and disability begins. These threshold points will be determined in different ways for different purposes. This is important epidemiologically since, for example, legal definitions of disability will establish the threshold for purposes of eligibility to support and services, differently across countries, and even between different ministries within countries. These definitions cannot provide the basis for internationally comparable disability epidemiology, which instead requires a standardized metric of functioning derived psychometrically. In terms of clinical practice, although there may be general agreement about when, for any domain, functioning is sub-optimal, good clinical practice recognizes that the level of functioning that a person experiences as disability will be shaped by personal and cultural expectations. Person-centered care requires that these expectations be respected, even if in the end they do not determine good clinical practice.

Disability – two societal perspectives

The ICF conceptualization of functioning and disability explains a persistent disagreement about the disability experience, reflected in two societal perspectives. (7) On the one hand, disability is clearly a universal feature of the human condition, in the sense that everyone will experience or is at risk of experiencing limitations of capacity and problems of performance in one or several domains of functioning. Although not everyone will experience a severe disability over the course of their lifespan, ageing itself is a process of accumulating impairments across many domains, often individually of low or moderate severity, but collectively quite limiting. That disability is universal therefore is simply a descriptive fact of the epidemiology of functioning. At the same time, however, primarily for socio-political reasons, we socially identify a group of individuals as ‘persons with disabilities’ as, effectively, a minority group who, as a group, have been marginalized from the mainstream and denied, to one extent or another, full inclusion and effective participation in society. This social problem is not universal, but is restricted to a separate minority.

The focus of rehabilitation is on the universal sense of disability. Because of population ageing – caused in part by the success of modern medicine and increased survival from disease and trauma – increasingly rehabilitation interventions are focused not only on severe assaults on functioning, such as stroke and Spinal Cord Injury (SCI), but also on situations of multiple, but relatively mild or moderate disabilities associated with the ageing process and linked to several health conditions, rather than a single severe disability directly associated with a single severe chronic health condition (23,24). The future challenge of rehabilitation as a health strategy, and PRM in particular, in the context of increased burden of care, increased costs of health and social care and greater social expectations of good health, will therefore be to create complex interventions strategies that respond to the entire experience of disability, involving several, diverse, domains of functioning. Equally important will be the evaluation of the outcomes of these interventions, in order to ensure quality and contain costs. But as a society – including rehabilitation professionals and professional organizations – we almost must address the concerns of those individuals living with disability who are excluded from fully participating in society. Here the focus is primarily on the social goal of full inclusion in line with basic human rights. These rights have been expressly reaffirmed for this social group by the 2006 United Nations’ Convention on the Rights of Persons with Disabilities. (25)

Rehabilitation

Rehabilitation, a main health strategy of the health system

From a health system perspective, rehabilitation is one of the four health strategies, (13) the goals and outcome indicators of which are shown in Table II.. Since the Declaration of Alma Ata in 1978 rehabilitation is considered an essential health strategy in primary care which aims to address “the main health problems in the community” by “providing promotive, preventive, curative and rehabilitative services”.(26)

The emergence of rehabilitation as the key health strategy of the 21st century

The curative, preventive and promotive health strategies were responsible for the growth in influence of medicine and public health for most of the 19th and 20th centuries. But towards the end of the last century epidemiological challenges emerged, principally because of the successes of previous decades. Specifically, the population was ageing because of better health care and increased survival for conditions previously considered lethal, and the non-communicable chronic diseases became, at least in the high resource world, the primary source of mortality.(27) In this century, as a consequence, besides maintaining the public health goal of prevention, the primary health strategy is not so much to cure as to optimize the functioning of people who are living longer, but with considerably more disability.(28,29) But this is the natural domain of rehabilitation, whose objective is to optimize intrinsic health capacity and enhance facilitating environments so that, in interaction, the outcome is more functioning and less disability. In effect, demographic and epidemiological realities have socially transformed rehabilitation into the key health strategy of the 21st century. (30)

Defining rehabilitation based on the ICF

The adoption of the International Classification of Functioning, Disability and Health (ICF) (4) has provided the framework for rethinking rehabilitation as a health strategy and putting rehabilitation on a firmer conceptual footing. A slightly modified part of an ICF-based conceptual description of rehabilitation published in 2007 by the professional practice committee of the UEMS-PRM section (13) was used as the definition of rehabilitation in the World Health Organization’s World Report on Disability (WRD) launched in 2011(31). See (Figure 3). In the same year, after an international discussion, ISPRM developed and endorsed an up-dated version of this conceptual description (14) See (Table III).

This conceptual description has also served as the basis for derived conceptualizations for specific applications. In particular, a derived version was developed for the medical specialty PRM, first in a version for international discussion (32), followed by a revised version endorsed by ISPRM in 2011 (15). See (Table IV). This conceptual description lends itself to the development of derived conceptualizations for specific areas of PRM, such as in relation to rehabilitation focusing on organ systems or health conditions. Finally, a second derived conceptual description has been developed for vocational rehabilitation (VR) (33). See (Figure 4).

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