Conceptual models have become a major focus of occupational therapy practice and education in the last two decades (American Occupational Therapy Association, Inc., 1973; Hagedorn, 1992; Dutton, Levy & Simon, 1993, Christiansen, 1991a; Reed, 1984; Reed & Sanderson, 1983). These conceptualisations are interpretations of the construct, ‘occupation’. Some conceptual models interpret occupation from the perspective of human function and describe the nature of human occupations (Gilfoyle, Grady & Moore, 1981; Kiehlhofner 1985; Reed, 1984, p. 491). The majority, however, interpret occupation from the perspective of occupational therapy, thereby forming the basis of practice models for intervention (Allen, 1985; Ayres, 1979). Despite the evolution of numerous conceptual models describing both human occupations and occupational therapy no single model has adequately met the range of theoretical, practice, and explanatory demands of the profession (Hubbard, 1991).

One conceptualisation of occupation that has been developing since 1972 (American Occupational Therapy Association, Inc., 1973) has been termed, “occupational performance”. Recently, this has evolved into both a framework which forms Guidelines for Client- Centered Practice (Canadian Association of Occupational Therapists, 1991), a terminology classification system (American Occupational Therapy Association, Inc., 1979, 1989; Dunn & McGourty, 1989), and a curriculum guide (American Occupational Therapy Association, Inc., 1974; School of Occupational Therapy, 1986, 1992). Individual theorists have begun to employ the term to describe the content and process of occupational therapy in different areas of practice (Árnadóttir, 1990; Christiansen, 1991; Dunn & Campbell, 1991; Llorens, 1984a; Mosey, 1981, 1986; Nelson, 1984, 1988; Pedretti & Pasquinelli, 1990). To date, conceptualisations of occupational performance have remained largely interventionist or practice focused (Árnadóttir , 1990; Pedretti & Pasquinelli, 1990; Söderbach & Ekholm, 1993) with little development of the notion of occupational performance as a way to explain dimensions of everyday human occupations.

This article describes an expanded model of occupational performance being developed by the authors, the Occupational Performance Model (Australia). Model development commenced in 1986 when it became clear that existing notions of occupational performance used to structure curriculum content in the Bachelor of Applied Science in Occupational Therapy course at Cumberland College of Health Sciences (now The University of Sydney) required expansion to more adequately reflect both the nature of human occupations and occupational therapy practice. In this article, discussion is limited to outlining the structure of the model by defining the major constructs and presenting a brief statement of the underlying assumptions relative to the nature of human occupational performance. Some aspects of the constructs and assumptions outlined are not new but reflect a synthesis of ideas about the nature of human occupations found in the literature (Meyer, 1922/1977; Christiansen, 1991, Llorens, 1991; Reed, 1984). Other aspects of the model extend these constructs and assumptions to form a new configuration of occupational performance that differs from notions currently in existence. Processes that exist within and between key elements and use of the model to explain occupational therapy practice will not be April, 1997, Monograph 1 2 addressed in this article.

Krefting (1985) suggests that for occupational therapy conceptual models attempt to answer the questions: what do therapists evaluate and treat, and why? Building conceptual models to answer these questions is viewed as an evolutionary process which begins with an idea (Reynolds, 1980). The process moves from idea to conceptualisation and involves a classification system in which a guiding set of concepts is developed. Finally, the conceptualisation evolves into relational statements that can be evaluated by agreement and inter-subjectivity of the professional community involved (Reynolds, 1980; Yerxa, 1983). The Occupational Performance Model (Australia) outlined in this article represents an example of the stage of model building where concepts have been developed, classified and related, but not yet fully evaluated or tested.

Dichoff, James and Wiedenback (1968) describe four developmental levels in model building that occur in practice disciplines such as occupational therapy. The most rudimentary level is “factor isolating”, wherein terminology is developed (1968, p.416). The second level is referred to as, “factor relating” whereby suggestions are made as to how concepts are interrelated. The third level includes, “situation relating” which identifies how the model is able to make predictions and specify the nature of the relationship. A “situation producing” model is a product of the fourth level and allows the model to be used prescriptively.

The Occupational Performance Model (Australia) has some characteristics of all the levels of model building outlined. Constructs in the model are named and defined (factor isolating); interactions between constructs are suggested (factor relating); propositions are made as to the association relationship which exists between constructs (situation relating); and the model can be used to establish goals and determine action or non-action (situation producing).

Concepts are the building blocks of conceptual models and can be identified as concrete, behavioural or abstract (Krefting 1985). The key concepts defined within each level of the model can be viewed as abstract and symbolic in nature and, therefore, are more correctly described as constructs. Relationships between constructs are referred to as principles (Payton, 1979). Relationships in this occupational performance model are depicted by arrows between constructs, and provide the hypothesised rules for action and future direction for research to verify the model.

The values, beliefs and principles underlying a conceptual model have a major influence on its identity and development. The assumptions underlying the Occupational Performance Model (Australia) fall into three broad categories: assumptions about human occupations, assumptions about human performance and assumptions about humans as self-organising systems.

Human Occupations

Assumptions about human occupations are derived from core philosophical tenets of occupational therapy which have been described by others (see for example: Canadian Association of Occupational Therapy, 1991; Christiansen, 1991; Hopkins, 1993, Keilhofner, 1995; Meyer, 1922/1977; Reed, 1984, 1993; Rogers, 1982). People are viewed from an wholistic perspective as being comprised of interacting elements of mind, body and spirit. Engagement in occupation provides a sense of reality, mastery, competence, autonomy and temporal organisation. Engagement in occupation involves an interaction between people and their environment. Health is not the absence of disease; rather it is competence and satisfaction in the performance of occupational roles, routines and tasks. Humans are active in the process of creating their occupational being or identity. This active participation can be intrinsically driven by choice or need, or externally imposed by environmental factors. An occupational being is that aspect of a human being that ideates and actualises engagement in occupational roles. This occupational being is expressed through occupational performance and ultimately defined by peoples’ occupational roles. Occupational Performance Model (Australia) 3

Performance

The term, ‘performance’, is usually assumed to mean action or motor performance: often the end product of other mental or psychological processes (Keilhofner, 1995; Nelson, 1988). The assumption underlying the model presented in this paper is that performance is more than ‘doing’. Delbridge (1981, p.1285) not only defines ‘performance’ as execution or doing, but more broadly defines performance as the way in which someone reacts under certain conditions, or fulfills a purpose. A reaction can be a physical, mental or emotional change. Purpose implies desire or motivation (Delbridge, 1981, p.722). ‘Performance’ in this model is therefore assumed to go beyond ‘doing’ to incorporate ‘knowing’ and ‘being’.

Self-Organisation

Humans are assumed to be self-organising systems that produce patterns of behaviour arising from the cooperative interaction of many elements (Kelso, Mandell & Schelsinger, 1989; Schöner & Kelso, 1988). This self-organisation is not necessarily explained by conceptual models of input-output mechanisms but rather by dynamic or non-linear systems. The underlying assumption of a dynamic view of behaviour is that humans are made up of a number of complex, multidimensional subsystems. No one subsystem has logical priority for organising or initiating the behaviour of the system. This assumption means that occupational behaviour at any one time occurs in response to the confluence of all the constructs outlined in the model, and that small changes in any one of the constructs can have major overall effects.

OCCUPATIONAL PERFORMANCE: CONSTRUCTS AND STRUCTURE

Consistent with other existing and evolving models in occupational therapy (Fisher, Murray & Bundy, 1991; Keilhofner, 1995; King, 1978; Llorens, 1976, 1984a; Mosey, 1981, 1986; Reilly, 1974), the primary focus of this model is the lifelong person-environment relationship and its activation through occupation (West, 1984).

Eight major constructs form the theoretical structure of this model. These are occupational performance, occupational performance roles, occupational performance areas, components of occupational performance, core elements of occupational performance, environment, space and time. Each of these constructs incorporates many interrelating elements.

In addressing a person-environment-performance relationship, the structural framework of the model considers the interactions between two environments relative to occupation: a person’s internal environment and the external environment (Fig. 1).

Figure 1: Relationship between the Internal and External Environment of Occupational Performance
The internal environment is composed of the aggregate structures, conditions and influences pertaining to occupational performance that are found within humans. In this model they include the constructs labeled occupational performance roles, occupational performance areas, occupational performance components, core elements of occupational performance and aspects of time and space. The external environment is composed of structures, conditions and influences that are outside the internal environment and within which occupations are performed. The external environment has sensory, physical, social and cultural dimensions that exist in time and space.

Structurally, occupational performance is viewed as an interactive system composed of aspects of the internal and external environment. All constructs within the system are interdependent in that the processes occurring between them form an ongoing dialogue within and between the two environments. This dialogue occurs within the context of space and time. April, 1997, Monograph 1 4 The interpretations of constructs in this model are made from two perspectives. One is an interpretation relative to the performance of occupations, and can be used to describe and classify the performance of human occupations. The other is an interpretation of the same constructs relative to the performer, and can be used to describe people as occupational beings.

CONSTRUCT 1: OCCUPATIONAL PERFORMANCE

The major construct around which the Occupational Performance Model (Australia) is conceptualised is occupational performance. The central proposition in this model is that all goaloriented behaviour related to daily living is occupational in nature. Performance, as defined in this model, extends the usual notions of performance from that of motor action only to include antecedent and subsequent physical, mental and emotional processes relevant to the task performed. Performance is the ability to perceive, desire, recall, plan and carry out occupations in response to demands of the internal and/or external environments. These occupations are characterised by purposeful changes in behaviour that can be physical, cognitive or psychosocial. Occupation refers to the purposeful and meaningful engagement in roles, routines, tasks and subtasks for the purpose of self-maintenance, productivity, leisure (Reed, 1984, p.492) and rest (Llorens, 1991, p. 46; Meyer, 1922/1977, p.641).

Occupational Performance is the ability to perceive, desire, recall, plan and carry out roles, routines, tasks and subtasks for the purpose of self-maintenance, productivity, leisure and rest in response to demands of the internal and/or external environment.

CONSTRUCT 2: OCCUPATIONAL PERFORMANCE ROLES

The concept of role is complex, composed of many different components and behaviours. Use of the term ‘role’ in this model is borrowed primarily from sociology literature (Jackson, 1972; Sarbin & Allen, 1968) and is defined as, “a set of behaviours that have some socially agreed upon functions and for which there is an accepted code of norms (Christiansen & Baum, 1991, p. 857). Roles are expressed by an automatic or deliberate assumption of behavioural patterns that are commonly associated with a specific function in society (Delbridge, 1981, p.1496). Roles function as vehicles for social involvement and productive participation and have been described as forming the nucleus of social interaction (Jackson, 1972; Vause-Earland, 1991).

Roles have been divided into broad groups in various ways that include such descriptors as family roles, personal-sexual roles, social roles, cultural roles and occupational roles (Thomas, 1966; Vause-Earland, 1991). Within the boundaries of each role acquired throughout life, expectations of performance of role related tasks are formed by both sociocultural factors in the external environment as well as the person who becomes the role performer. Competence and satisfaction with role performance is therefore based on internal as well as external perceptions of performance (Christiansen, 1991; Jackson, 1972). Role behaviour is viewed as the way people express their place in society, both in terms of their unique and valued contribution and their ability to conform to the code of personal acceptability within a particular sociocultural environment.

Occupational performance roles are those roles that constitute the bulk of daily function and routines (Keilhofner, 1995; Keilhofner & Burke, 1985; Llorens, 1991). There is increasing emphasis in occupational therapy literature that the goals of the profession include the preservation, maintenance and development of valued occupational roles (Christiansen, 1991; Heard, 1977; Jackoway, Rogers & Snow, 1987; Keilhofner, Harlan, Bauer & Maurer, 1986; Matsutsuyu, 1971; Moorhead, 1969; Oakley, Keilhofner, Barris & Reichler, 1986; Vause- Earland, 1991; Versluys, 1980).

The concept of ‘choice’ and ‘need’ that drives people to engage in occupational roles reflects the extent to which any occupational role can be chosen by an individual or assumed as a result of social press. This Model recognises that, as both a construct and a personal/social system of values, individual choice is alien to a number of social groups whose sociocultural identity is Occupational Performance Model (Australia) 5 collectivist (Manstead & Hewstone, 1995). The individual, the social group or combinations of both, can therefore determine occupational role performance.

Occupational performance roles are composed of patterns of occupational performance that are determined by a person’s requirements of daily routines of self-maintenance, productivity, leisure and rest within specific sensory, physical, cultural and social contexts.

Consistent with the person – environment – performance relationships outlined in the model, occupational performance roles can be conceptualised as having three dimensions. One is ‘knowing’. Knowing is having an intuitive or concrete understanding of desired or expected occupational performance roles. This knowing results in a person having ideas about organised patterns of occupational performance that are expected or accepted by the physical-sensorysociocultural environment. The second involves a process of doing and, usually entails the physical action of people within their environment. The third dimension addresses the interpersonal and socioemotional aspects of role identity and acknowledges the notion of ‘being’ as a fulfillment or satisfaction component of occupational performance roles (Rowles, 1991).

It is possible that this dimension is linked to personal meaning, which contributes to valuing one’s occupational role.

People; participate fully or partially in the performance of occupational performance roles. For example, full participation in the occupational performance role of a homemaker (work role) produces occupational behaviour involving the manipulation of physical aspects of the household (doing). This may or may not be carried out within the social context of family members requiring interpersonal interaction (environment), and personal knowledge of their needs (knowing). The role carries with it aspects of satisfaction and fulfillment that are linked both to personal notions of competence in the performance of the role and personal perceptions of its sociocultural worth (being).

Alternatively, an elderly man who requires considerable physical assistance may be deemed to have no occupational performance role as a self-maintainer because he can no longer ‘do’ selfmaintenance routines or tasks. However, he does ‘know’ what he wants done and how he wants it done by his carers, thereby participating in the ‘knowing’ dimensions of role performance. He can also experience satisfaction when routines are carried out to his specifications and experience the ‘being’ dimensions of role function in terms of fulfillment. Others may be able to carry out all the ‘doing’ and ‘knowing’ aspects of occupational performance roles but never achieve the expected feelings of satisfaction and fulfillment from performance. The ‘being’ dimension of this role performance would be missing.

Someone with severe and multiple disabilities may not be able to contribute to the ‘doing’ or ‘knowing’ aspects of an occupational role such as self-maintainer. Personal expectation may be related to ‘being’ cared for in a safe, comfortable situation that provides satisfaction and contentment to the level needed by that person. As stated before, assumption of occupational performance roles are partly determined by a person’s environment. In this instance someone who lacks the ability to organise the ‘doing’ or ‘knowing’ aspects of occupational performance roles are vulnerable to ‘being’ cared for at a level that is deemed appropriate by the sociocultural context. This may or may not be congruent with personal expectation.

Roles depend on changing personal-performance components such as age, ability and physicalsensory- sociocultural circumstance, and most people assume a considerable number of roles simultaneously. The way people balance the configuration of roles at any one time, and the decision about which roles are discarded and which roles are assumed, form transitions in occupational role behaviour that are constantly made throughout the lifespan in response to demands of the internal and external environment.

As part of an interactive system, occupational performance roles have the capacity to simultaneously influence and are influenced by other aspects of the system. For example, in many cultures a person’s occupational performance role as a worker determines the balance of self-maintenance, productivity, leisure and rest areas of occupational performance. These, in turn, determine the component requirements necessary for performing in the April, 1997, Monograph 1 6 productivity area. Alternatively, when circumstance allows a person to choose an occupational performance role, the choice may be based on particular component strengths, such as the outstanding motor coordination of an athlete. Occupational Performance Role is the central organising construct of occupational performance in the Occupational Performance Model (Australia) (Chapparo & Ranka, 1996) (Fig. 2).

Figure 2: Position of Occupational Roles in the Occupational Performance Model.

Occupational Performance Roles are patterns of occupational behaviour composed of configurations of self maintenance, productivity, leisure and rest occupations. Occupational Performance Roles are determined by individual person-environment performance relationships. They are established through need and/or choice and are modified with age, ability, experience, circumstance and time

Analysis of Occupational Performance: Occupational Performance Roles
Any analysis of dimensions of occupational role performance relative to this definition would include the following dimensions:

• Identification of chosen and needed occupational performance roles
• Environment – occupational performance role ‘fit’.
• personal notions of the balance of occupational performance roles that are chosen and needed.
• ‘Doing’ – the physical capacity to carry out routines required by an occupational performance role.
• ‘knowing’ – the capacity to create, plan, structure and organise routines required by an occupational performance role.
• ‘being’ – the derived or expected satisfaction, value and fulfillment attributed to perceived occupational role performance.
• perceived appropriateness of identified occupational performance roles by the person and others in their environment with consideration of age, ability, environmental resources and time.
• potential for adaptation or change in occupational role performance.

CONSTRUCT 3: OCCUPATIONAL PERFORMANCE AREAS

Occupational therapy has traditionally categorised performance of daily occupations to three areas: self-maintenance occupations, productivity/school occupations and leisure/play occupations. This model proposes a fourth area: rest occupations. Others have also recognised its importance as a dimension of occupational performance (Llorens, 1991) (Fig. 3).
Rest Occupations refer to the purposeful pursuit of non-activity. This can include time devoted to sleep (Meyer, 1922/1977), as well as routines, tasks, subtasks and rituals undertaken in order to relax.

Inclusion of this category as separate from selfmaintenance occupations acknowledges that there are sociocultural, daily and life span reasons for the degree to which people are, or wish to be, passive and contemplative rather than active and productive (Rowles, 1991). For example, people who are growing older may have an increasing desire and ability for reminiscence, life review and more reflective modes of occupation (Coleman, 1986; Rowles, 1991).

Self-Maintenance Occupations are routines, tasks and subtasks done to preserve a person’s health and well-being in the environment (Reed 1984, p.499) Occupational Performance Model (Australia) 7 These routines, tasks and sub-tasks can be in the form of habitual routines (dressing, eating) or occasional nonhabitual tasks (taking medication) that are demanded by circumstance.

Productivity/School Occupations are routines, tasks and subtasks that are done to enable a person to provide support for self, family or community through the production of goods or provision of services (Reed, 1984, p.499).

Leisure/Play Occupations are those routines, tasks and subtasks that are done for purposes of entertainment, creativity and celebration.

Figure 3: Occupational Performance Areas and their relationship to other constructs in the Occupational Performance Model.

Occupations: Subtasks, Tasks & Routines

Although activity has been a term traditionally used in occupational therapy to denote purposefulness of action (Christiansen, 1991; Cynkin, 1979; Fidler & Fidler, 1978; Meyer, 1922/1977; Mosey, 1981). Meanings attributed to the underlying construct have become so broad and flexible that it has lost its power to 1) describe elements of occupations and performance at varying levels, and 2) to direct and influence the focus of occupational therapy intervention (Christiansen, 1991; Jenkins, 1993; Lyons, 1983; Nelson, 1988). At this point in the development of the Occupational Performance Model (Australia) occupations in each occupational performance area have been classified according to the existing complexity of structure and time (Fig. 4).

Figure 4: Structure of Occupations in the Occupational Performance Model: Routines, Tasks and Subtasks.

First, the structure of an occupation can be viewed from three levels of complexity: subtasks, tasks and routines. Subtasks consist of steps or single units of the total task and are stated in terms of observable behaviour (Romiszowski, 1984). Tasks are viewed as sequences of subtasks that are ordered from the first performed to the last performed to accomplish a specific purpose. These tasks can be carried out in action or thought (planned or imagined). For example, drinking can be divided into subtasks such as locating the glass, reaching for the glass, grasping the glass and lifting the glass. All of these subtasks, when put together in an orderly sequence, result in execution of the total task: drinking.

Routines are sequences of tasks that begin in response to an internal or an external cue and end with the achievement of the identified critical function (Brown, 1987). The task patterns that are created can be fixed or flexible. Many selfmaintenance routines are fixed. For example, toileting, oral-facial hygiene or getting dressed requires very definite tasks to be performed in April, 1997, Monograph 1 8 order to accomplish the critical function. The prevailing sociocultural context will determine how the routines are fixed and there is usually little deviation from the accepted routine. Flexible routines can be accomplished in many different ways (Brown, 1987). As long as it is accomplished in a way that is acceptable to the performer and others, it doesn’t matter what the task pattern is. For example, play routines involve a number of tasks that can assume different structures, such as playing soccer, going to the movies, or painting a picture. Each of these play routines accomplishes the same critical function: play.

All routines are composed of flexible subtasks and sequences. For example, although dressing is not a flexible routine, the specific subtasks that are used for the routine of dressing can vary. One person buttons her blouse using a buttonhook, another person pre-buttons his and puts it on over his head, and yet other people may use Velcro fasteners.

The classification of subtasks, tasks and routines can also be described according to their temporal patterns. Routines can be regular or intermittent. Regular routines occur on a daily basis and are usually critical to a person’s function relative to the demands of his or her environment. They can often become habitual whereby the routine of well-practiced sequences of tasks can be performed without thinking. Intermittent routines do not have the same regularity. They do not have to be accomplished every day but may still be crucial to independent functioning. For example, sudden illness prompts a person to engage in the routine of going to the doctor. Other intermittent routines may never need to be carried out but have a qualitative impact on the person’s life. For example, going to the movies is not a critical routine for most people but may be perceived by some as life enriching. Many people seek the novelty of an intermittent routine.

The extent to which people participate in performance of subtasks, tasks and routines varies throughout the lifespan and is dependent upon age, circumstance and ability. For example, young children are unable to complete routines without assistance from parents and teachers. However, from quite early in their life they can complete some tasks that are part of routines and many subtasks. Within the first three months of life babies are participating in subtasks that involve locating mother’s face, reaching for toys and bringing objects to mouth. Many people who have reduced motor and/or cognitive ability may never be able to master the performance of daily routines. However, having the opportunity to choose to participate in part of the routine (tasks) or even subtasks contributes to them establishing an occupational identity that is linked to an occupational performance role. For example, a young man with cognitive impairment who is unable to calculate the cost of food or construct a shopping list need not be excluded from participating in the entire routine of shopping. His participation in the tasks and subtasks of the shopping routine which he is able to master, such as traveling to the store, selecting items, packaging items and transporting them contributes to extending his occupational identity by participating in the occupational role performance of a shopper.

Classification of occupations: An idiosyncratic process

Beyond this broad structure it is not possible for an observer to generate a static classification of occupations for each occupational performance area based on knowledge of a specific routine, task or sub-task alone. The classification process is an idiosyncratic function that is done by the performer. The way a person classifies any one occupation may change from day to day relative to its purpose. For example, reading may be classified by a person at one time as a selfmaintenance occupation (to read prescription instructions), or as a work-related occupation (to read a computer screen), or as a leisure occupation (to read a book for enjoyment), or in the specific pursuit of rest (reading in order to get to sleep). Routines are similarly self-classified. A routine is given meaning by the context in which it is performed or the personal intent of the routine. For example, cleaning the floor may be thought of as a self-maintenance occupation relative to maintaining environmental hygiene. If the intent, however, is to perform the same routine as a professional cleaner, some of the tasks and subtasks needed to perform the routine would change.

Moreover, classification of occupations varies between sociocultural groups. For example, some cultures may never define what they are doing as leisure (Anderson, 1964; Ranka & Zhuo, 1987; Ranka, Henley & Zhuo, 1989) even though Occupational Performance Model (Australia) 9 others may interpret various occupations being performed as ‘celebrating’ or ‘playful’. Similarly, people in other cultures (eg. Soloman Islanders) may define everything they do as selfmaintenance (Twible, personal communication, February, 1988; Twible & Henley, 1996) even though observers may note a productivity purpose. Therefore, the classification of occupations is self-defined and depends on the context, the intent of the performer and the nature of the task (Nelson, 1988; Christiansen, 1991). The dotted lines that separate the occupational performance areas of self-maintenance, rest, leisure and productivity in Figure 3 illustrate that in the Occupational Performance Model (Australia) this division is artificial.

Each day throughout the lifespan is characterised by the performance of patterns of selfmaintenance, productivity, leisure and rest occupations. The amount, type, and duration of performance in one area influences performance in the other areas. This is illustrated by the dotted lines contained within the Occupational Performance Areas level of the Model (Fig. 3). For example, the amount of work that the performer is required to do on a daily basis may determine the amount of rest the person requires, or the time available for leisure. The pattern of occupation in each of the areas over time is individually determined relative to desired or expected occupational role performance. Contrived notions of the balance of occupational performance at this level cannot be externally imposed.

This Model proposes that a relationship exists between occupational performance roles and occupational performance areas and that the nature of this relationship is interactive. This is depicted in Figure 3 by the arrows between these levels in the Model. On the one hand, performance in occupational areas contributes to the motivation and context for development of occupational performance roles. Alternatively, occupational performance role responsibilities help to define the nature of performance in the occupational areas.

Analysis of Occupational Performance: Occupational Performance Areas

Analysis of occupations at this level can be analysed and described according to both the elements of the routine, task or sub-task being done (task demands analysis) and the performance (behavioural task analysis). For each element both structure and timing can be analysed. For example, cooking can be described as a routine occupation that requires performance of the tasks and subtasks of cutting, reading, stirring, tasting and grasping objects in such a way that a meal is produced within a specific time frame (task demands analysis). The person producing the meal can be analysed as to how successful and satisfying performance of these routines, tasks and subtasks are relative to both structural and timing goals (behavioural task analysis).

Dimensions of analysis that would be required in occupational performance areas include:

• identification of routines, tasks and subtasks that support needed andchosen occupational roles.
• analysis of the structure and timing of sub-task and task performance.
• analysis of the structure of routine performance, including the mastery ofperformance of fixed and flexible routines.
• analysis of the timing of routines including both regular and intermittentroutines.

CONSTRUCT 4: OCCUPATIONAL PERFORMANCE COMPONENTS

Accomplishment of routines and tasks in the occupational performance areas is predicated on the ability to sustain efficient physical, psychological and social function. This aspect of the model is conceptualised as forming both the component attributes of the performer as well as the components of occupational tasks. For example, there are physical, sensory-motor, cognitive, and psychosocial dimensions to any task performed. These dimensions mirror and prompt a person’s various physical, sensorymotor, cognitive and psychosocial operations that are used to engage in task performance. Observation and analysis of occupational performance components can either focus on the task and sub-task components of performance (task demands analysis) or the person components of performance (behavioural task April, 1997, Monograph 1 10 analysis) and the relationship between the two. Occupational performance components are broadly classified into five component areas: biomechanical, sensory motor, cognitive, intrapersonal and interpersonal (Fig. 5).

Figure 5: Components of Occupational Performance and their relationship to other constructs

Biomechanical Component: From the perspective of the performer this component refers to the operation and interaction of and between physical structures of the body during task performance. This can include range of motion, muscle strength, grasp, muscular and cardiovascular endurance, circulation, elimination of body waste. From the perspective of the task being done this component refers to the biomechanical attributes of the task; for example, size, weight, dimension and location of objects.

Sensory-Motor component: From the perspective of the performer this component refers to the operation and interaction of and between sensory input and motor responses of the body during task performance. This can include regulation of muscle activity, generation of appropriate motor responses, registration of sensory stimuli and coordination. From the perspective of the task this component refers to the sensory aspects of the task. For example, gravity, colour, texture, temperature, weight, movement, sound, smell and taste.

Cognitive Component: From the perspective of the performer this component refers to the operation and interaction of and between mental processes used during task performance. This can include thinking, perceiving, recognising, remembering, judging, learning, knowing, attending and problem solving. From the perspective of the task this component refers to the cognitive dimensions of the task. These are usually determined by the symbolic & operational complexity of the task.

Intrapersonal Component: From the perspective of the performer this component refers to the operation and interaction of and between internal psychological processes used during task performance. This can include emotions, self-esteem, mood, affect, rationality and defense mechanisms. From the perspective of the task this component refers to the intrapersonal attributes that can be stimulated by the task and are required for effective task performance such as valuing, satisfaction and motivation.

Interpersonal Component: From the perspective of the performer this component refers to the continuing and changing interaction between a person and others during task performance that contributes to the development of the individual as a participant in society. This can include interaction among individuals in relationships such as partnerships, families, communities and organisations both formal and informal. Interactive examples include sharing, cooperation, empathy, verbal and nonverbal communication. From the perspective of the task this component refers to the nature and degree of interpersonal interaction required for effective task performance. The impact of components on occupational Occupational Performance Model (Australia) 11 performance is the result of a complex network of interactions involving interdependent relationships between the components themselves as well as between each component and other constructs within the model. The capacity of the components to influence each other is illustrated by the dotted lines contained within this level of the Model (Fig. 5). The arrows between levels in the Model (Fig.5) illustrate the interaction between the components and other levels of the model.

Analysis of Occupational Performance: Components of Occupational Performance

There are many analyses occupational therapists use to determine the efficacy of occupational performance at this level of the model. For example, goniometry can be used to analyse biomechanical operations of range of motion (Trombly & Scott, 1989); recall of digit-span can be used to analyse short-term memory operations (Duchek, 1991); maintenance of body position on a balance board is an example of one sensorymotor operation (Fisher, Murray & Bundy, 1991); measures of social interaction can be used to analyse interpersonal operations (Mosey, 1986); and loneliness or depression inventories are described as measures of intrapersonal operations (Borg & Bruce, 1991). However, Leont’ev (1978) reminds us that it is impossible to analyse many of these operations independent from the context in which they are embedded. Each operation has an interaction with other operations. Therefore, analysis at this level requires:

• identification of component operations that support task and routine performance in the everyday world.
• the effect of one component on other component operations be considered.
• consideration of the task demands and the ‘fit’ between these and the component operations of the performer.

CONSTRUCT 5: CORE ELEMENTS OF OCCUPATIONAL PERFORMANCE

This construct acknowledges the body-mindspirit interactionist paradigm that has long been recognised as key to physical and mental health and well being (Townsend, Brintnell & Staisey, 1990) (Fig. 6).

Figure 6: Core Elements and their relationship to other constructs in the Occupational Performance Model.

Although each aspect of this construct is described in this section, they cannot be functionally separated, reduced, or understood as unique elements. This is not a new concept in occupational therapy. In 1922, Meyer (1922/1977) advocated this premise by stating, “our body is not merely so many pounds of flesh and bone figuring as a machine, with an abstract mind or soul added to it” (1922/1977, p.640). Instead, he described the process of ‘doing’ and ‘knowing’ as, “pleasurable ease” (1922/1977, p. 640). Although never defined by Meyer, pleasurable ease could be interpreted from the perspective of research in psychoneuroimmunology that has linked alterations of mood, pain and pleasurable response to a variety of both mental and physical activities (Ader & Cohen, 1993; Pelletier & Herzing, 1988). In this model, body, mind and spirit are viewed as core elements both corporeal (physical and tangible) and incorporeal (intangible and without material existence).

Acknowledging the core element of the physical body affirms that within the boundaries of our understanding, aspects of human performance can be described in terms of their smallest known structure such as cells, molecules and tissues. April, 1997, Monograph 1 12

The interaction within and between these structures contributes to occupational performance by providing the intrinsic physical elements required for occupational performance.

Body Element is defined as all of the tangible physical elements of human structure.

The core element of the mind has been conceptualised by theorists in many different forms. Some models of the mind are simple, mechanical and reductionist, and compare the human mind to a simple input-output model. Other approaches attempt to describe the mind by means of biological processes such as neuronal models. Still other models of the human mind are more abstract. Fischbach (1992), for example, equates the mind with consciousness, or a subjective sense of self-awareness. He uses the metaphor of ‘the mind’ as, “a vigilant inner core that does the sensing and moving…and produces urges, moods, desires and subconscious forms of learning” (Fischbach, 1992, p.24-25). Most theorists agree that the product of the mind is thought which, in turn, produces the individual paradigms of reality from which we plan our daily routines, tasks and subtasks.

Mind Element is defined as the core of our conscious and unconscious intellect that forms the basis of our ability to understand and reason.

The notion of spirituality as a fundamental essence of a person was applied to occupations by Egan and DeLaat (1994) who described human spirituality as the essence of a person that is expressed in everyday actions. This view mirrors earlier interpretations of spirituality in occupation as expressed by Meyer (1922/1977) who observed that as people live their life through daily occupations, they concern themselves, not only with the performance of occupations but with deriving meaning from them. Spirituality, as distinct from religiosity, therefore, is not viewed as separate from everyday occupations, but as a part of every level of occupational performance.

Although many idiosyncratic definitions of spirituality have been derived in health literature, three concepts appear to recur and relate to notions of ‘meaning’ (Dossey & Guzzetta, 1994), ‘hope’ (Bruhn, 1984; Dufault & Martocchio, 1985; Fine, 1991; Forbes, 1994) and a sense of ‘interconnectedness’ (Canadian Association of Occupational Therapists, 1991). The link between human occupations and meaning is at the heart of ‘purposefulness’ of life.

Within the Occupational Performance Model (Australia), spirituality is expressed in all constructs. At the level of occupational performance routines, tasks and subtasks it contributes to the person’s perception of meaning and purpose when creating, thinking about, and doing desired and needed occupations. People, in carrying out occupations either in thought or action feel compelled to create and develop their inner purposefulness (Breines, 1989; Urbanowski & Vargo, 1994). At this level, where occupational performance is not perceived as having purpose, it becomes meaningless, lacking ‘spirit’. Philosophers have suggested that loss of meaning is perhaps the greatest personal and collective crisis facing people in everyday life (See for example, Frankl, 1959; Fromm, 1968; Marx, 1932/1977; Popper, 1981; Trueblood, 1951). For example, Trueblood (1951, p.49) stated, “What is terrible for men and women is the conviction that they are not needed, that they contribute nothing, and that their lives add up to no enduring meaning”.

At the component level in the Occupational Performance Model, spirituality, as defined through meaning and hope, contributes to cognitive operations that involve imagination, decision-making and the ability to reflect. Intrapersonal aspects of meaning and hope relate to notions of a personal locus of control, intention, will, motivation. Interconnectedness is fundamental to the desire for and the development of interpersonal operations that simultaneously satisfy a personal need and ‘fit’ with the external social world.

At the level of occupational role performance, spirituality in terms of personal meaning, connectedness and hope contribute to the ‘being’ dimension of roles and the satisfaction derived from carrying out chosen or needed roles.

Feeling hope through an imagined future is a dimension of time. Reminiscence through time gives people a connectedness with their past and affirms perceptions of their life meaning. Ultimately, peoples’ personal life stories, embedded in occupation, allow them to connect Occupational Performance Model (Australia) 13 to universal visions of themselves, as they are liked to whole societies, cultures and traditions.

Early in the history of the profession, spirituality was recognised as an integrated aspect of human function and inseparable from mind/body elements. Subsequent development in the profession has devalued this aspect of human function to the point where it is ignored. This model does not view spirituality as one human subsystem, but a fundamental core element that is embedded in all aspects of occupational existence. It is viewed as being highly personal, and at the same time, linking people to others and allowing them to create their own personal notions of humanity. Spirituality refers to the existential aspect of humans that acknowledges an existing ‘mystery’ to life. The acknowledgment of a spiritual dimension presupposes that humans engage in reflection on the nature and meaning of their lives (Canadian Association of Occupational Therapy, 1991; de Rozario, 1994). Many myths and beliefs are expressions of spirituality. Some authors suggest that these are our attempts to explain the world to ourselves. What this construct acknowledges is the experience of consciousness, of will and of harmony that influences every aspect of human performance (Kuhn, 1962; Popper, 1981). For centuries, philosophers have linked the spiritual dimension of humans with the development of ethical contexts for human behaviour which in turn, is linked to many of the sociocultural norms that determine how we perform daily occupations.

Acknowledgment of a spiritual dimension to human occupational performance in this model is not a rejection of physicalist explanations of human behaviour, but an affirmation that at this stage in human knowledge development, physical explanations are incomplete.

Spirit Element is defined loosely as that aspect of humans which seeks a sense of harmony within self and between self, nature, others and in some cases an ultimate other; seeks an existing mystery to life; inner conviction; hope and meaning.

Together the body, mind, and spirit form the human body, the human brain, the human mind, the human consciousness of self and the human awareness of the universe (Popper, 1981). Relative to occupational performance, the bodymind- spirit core element of this model translates into the ‘doing-knowing-being’ dimensions of performance. These doing-knowing-being dimensions are fundamental to all occupational performance roles, routines, tasks and subtasks and components of occupational performance. That interaction can occur between the core elements is illustrated by dotted lines contained within this level of the model. The arrows which link the Core Elements to the Occupational Performance Components (Fig. 6) reflect the influence between the core elements and other levels of the model.

Analysis of Occupational Performance: Core Elements of Performance

Analysis of occupational performance at this level makes reference to:

• specific body system pathology that interferes with occupational performance such as swelling, soft tissue shortening, inflammation, compromised cardiovascular system pathology, compromised respiratory system pathology and other compromised body systems.
• specific pathologies of the mind which arise from compromised central nervous system function and interfere with occupational performance such as disordered neuronal transmission, brain damage and disordered neurochemistry.
• specific pathologies of the spirit which interfere with occupational performance such as loss of hope, loss of resolve, loss of ‘connectedness’, loss of purpose

CONSTRUCT 6: EXTERNAL ENVIRONMENT

The external environment is all the conditions surrounding a person, and has been classified in various ways. This model categorises the external environment as an interactive sensoryphysical- sociocultural phenomenon (Fig. 7).

The interaction of these four environmental dimensions creates further sub-dimensions such as political and economic environments that act as a filter between the internal and external April, 1997, Monograph 1 14 environment and profoundly affect occupational performance. Although aspects of this environment are defined separately, the environmental impact that is brought to bear on occupational performance is an integration of sensory, physical, social and cultural dimensions (Llorens, 1984b, Spencer, 1987). Arrows connecting all four dimensions of the external environment reflect this.

Physical aspects of the environment refer to the natural and constructed surroundings that form physical boundaries. This physical environment contributes to shaping occupational performance by influencing the extent to which selfmaintenance, productivity, leisure and rest occupations can be performed. Although the physical environment is often viewed as tangible, it is partially shaped by other environmental dimensions. For example, sociocultural environmental influences determine the way a physical environment looks. A large city in a western society with its tall buildings made of glass and steel has quite different physical dimensions to a tropical village on a Pacific island. Sensory aspects of the environment also contribute to its physical characteristics. Differences in the style, structure and physical components of an Arctic environment are quite different to those in a desert environment.

Figure 7: External Environment and its relationship to other constructs in the Occupational Performance Model

The sensory environment links most directly to the sensory and cognitive components of the internal environment and provides the natural cues that direct occupational performance. Fundamental to information supplied by the sensory environment is information about its survivability. For example, determining whether an environment is too hot or too cold to sustain life; too noisy to support rest or work occupations or too visually confusing to support concentration. Occupational Performance Model (Australia) 15

Culture here refers to transmitted patterns of behaviour shared by members of a group which provide them with effective mechanisms for interaction (Krefting & Krefting, 1991). Culture can be thought of as an overriding concept (eg. western cultures and indigenous cultures) that directs the sociocultural specificity of group environments each with its own beliefs and rituals that are used to determine behavioural norms.

Humans are social creatures. Some theorists have suggested that the social environment is constructed of several layers (Llorens, 1984b; Barris, Keilhofner, Levine & Neville, 1985). These layers have been developed based on notions of degrees of intimacy occurring between people in a family, neighbourhood, community and wider society (Llorens, 1984b). Many occupational performance roles are carried out within differing social environments that carry with them codes of behaviour in the form of expected social roles. Occupational performance roles established within these social environments and the level of mastery is not only based on individual choice but also on social expectations. Therefore, one of the major influences on occupational role performance is the degree of fit between occupational performance roles and the social environment.

The relationship that exists between the previous constructs and the external environment is profound and complex as illustrated in Figure 7. Many occupational performance roles, routines, tasks and subtasks are performed specifically in response to external demands leading to constant adaptation of occupational behaviour. Similarly, occupational performance which occurs within the external environment, can function to maintain environmental influences or change them. This adaptation process can be observed or analysed from the perspective of the impact of environmental dimensions on occupational performance and/or the impact of the performer on the environment.

Physical Environment refers to the natural and constructed surroundings of a person, which form physical boundaries and contribute to shaping behaviour.

Sensory Environment refers to the sensory surroundings of a person. Sensory aspects of the environment give a person information about the physicalsociocultural aspects of the environment and its survivability.

Cultural Environment refers to an organised structure which is composed of systems of values, beliefs, ideals and customs which are learned and communicated to contribute to the behavioural boundaries of a person or group of people.

Social Environment refers to an organised structure created by the patterns of relationships between people who function in a group which in turn contributes to establishing the boundaries of behaviour.

Analysis of Occupational Performance: External Performance Environment

Analysis of occupational performance at this level of the model considers:

• the degree to which present and future performance environments interfere with occupational role performance and the degree to which they support it.
• the potential for modification of the physicalsensory- sociocultural environment. Transactions within the six constructs already outlined occur within dimensions of space and time.