The Tidal Model: analysis based on Meleis’s perspective Teoría de la Marea: análisis pautado en la perspectiva de Meleis REFLEXÃO

Objective: To critically refl ect on the conceptual components of the Tidal Model in the application of the mental healthcare process. Method: Critical analysis based on the Models of Theory Analysis, focused on the clarity and consistency of the theoretical components of the Tidal Model. Results: The clarity of the theory was verifi ed through the demonstration of the following components: functional, presuppositions, concepts and propositions. The consistency is due to the possibility of proven application in several countries with different populations. Conclusion: There is a vast fi eld of research and possibilities of application in the Brazilian nursing consultation, in search of usefulness and support in nursing care. Descriptors: Nursing; Nursing Theory; Mental health; Models of Nursing; Evaluation. RESUMEN Objetivo: refl exionar críticamente acerca de los componentes conceptuales de la Teoría de la Marea en aplicación del proceso de cuidados en salud mental. Método: análisis crítico fundamentado en el Modelo de Evaluación de Teorías, enfocado en la claridad y consistencia de los componentes teóricos de la Teoría de la Marea. Resultados: se constató la claridad de la teoría por medio de la demostración de componentes funcionales, presupuestos, conceptos y proposiciones. La consistencia ocurre por la posibilidad de aplicación comprobada en diversos países con diferentes poblaciones. Conclusión: hay un amplio campo de posibilidades de investigación y aplicación en la consulta de enfermería brasileña, en búsqueda de utilidad y respaldo en el cuidado de enfermería. Descriptores: Enfermería; Teoría de Enfermería; Salud Mental; Modelos de Enfermería; Evaluación. Teoria da Maré: análise pautada na perspectiva de Meleis The Tidal Model: analysis based on Meleis’s perspective Teoría de la Marea: análisis pautado en la perspectiva de Meleis REFLEXÃO Liane Araújo Teixeira E-mail: lianeteixeiras@hotmail.com AUTOR CORRESPONDENTE


INTRODUCTION
The nursing process is conducted through systematic actions, in view of obtaining positive results, and it takes place through the implementation of a therapeutic plan, supported scientifically with actions based on nursing theories.
Nursing theories articulate the work of nurses and their functions in care, offering insight into the philosophical foundations of nursing.In addition, they present descriptions of how to help patients become comfortable, such as completing treatment with as little damage as possible and achieving the highest level of health.In general, individuals have needs, and nursing care must perceive them and intervene (1) .
As observed, the evaluation of a theory constitutes an essential component both for nursing practice and for the development of knowledge, since it chooses the most appropriate theory to be used as a tool for research, teaching, administration and consultation.In addition, the evaluation identifies effective theories for exploring specific aspects of practice, or to guide the research; compares and contrasts different explanations of the same phenomenon; improves the potential of building change, and further develops theory.It also identifies, epistemologically, approaches of a subject by means of focusing on the sociocultural context of the theory and theorist (1) .
Thus, the relevance of a nursing theory in care practice or lack thereof should be analyzed.There are several models of analysis of theories and, in this essay, Meleis' Models of Theory Analysis.

OBJECTIVE
To critically reflect on the theoretical components of Phil Barker's Tidal Model in the context of the mental health care process.

METHOD
This is a critical analysis of the Tidal Model, based on Meleis's Theory Evaluation Model, which can be used in whole or in part, consisting of five segments: description, analysis, criticism, testing and theory support (1) .
As this study proposed to perform a critical analysis of the Tidal Model, the researchers focused on the third stage of the evaluation method, in the criteria of relation between structure and function, and the units of analysis clarity and consistency were debated on.These components should be clear and objective so that the proposal is considered a nursing theory.
This study appointed the criteria of relation between structure and function.This relation is committed to the development of a critical evaluation, judging the relation between different components of a theory, such as functional components, presuppositions, concepts and propositions.The criteria for critical analysis of the clarity, consistency and usefulness of the theory were addressed (1) .
The Tidal Model was chosen to be analyzed due to its conceptual basis in mental health, a research area with which the researchers are familiar with.This is a theory that has been effectively worked with internationally, with several successful projects, but not yet translated into Portuguese (1) .Thus, the critical analysis of the Tidal Model enables researches, teaching and practices based on this theory in Brazil.
The study was conducted from August to December 2015 and it was designed in the Postgraduate Program in Clinical Care in Nursing and Health, PhD level, during the subject of Critical Analysis of Clinical Care in Nursing and Health as a method of assessing the knowledge acquired in the course.

Critical analysis of the Tidal Model
For the critical analysis of a theory, one must consider the relation between structure and function, the diagram of the theory, the contagion circle, usefulness and external components (1) .
As mentioned, the relation between structure and function is connected to the development of a critical evaluation: it is the one responsible for analyzing the relation between different components of a theory, such as functional components, presuppositions, concepts and propositions.Severe criteria should be taken into account, such as clarity, consistency, simplicity/complexity, and tautology/theology (1) .
Clarity is the demonstration of presuppositions, concepts and propositions, in addition to the functional components.In order to have clarity on the concepts, theoretical and operational definitions are necessary, giving consistency to the whole theory, as they are present in a parsimonious and coherent way with the assumptions and propositions of the theory (1) .
In view of a better understanding of clarity, the functional components, presuppositions, concepts and propositions of the Tidal Model, which support the functional analysis of the Meleis Models of Theory Analysis, have been described in charts.
The focus is on the functional components, which are defined as follows: client, nursing, health, nurse-patient interaction, environment, nursing problems and nursing care.

Focus
To identify what needs to be done to help the person address, solve, overcome or adapt to the problems of life associated with what might be called their "mental illness" or "psychiatric disorder" (2) .

Client
The human being is represented by the physical, emotional, intellectual, social and spiritual dimensions.Recovery is possible, and change is inevitable because nothing is lasting in the perspective that the individual will always be changing.The individuals always know what is best for them.They have the necessary resources for their recovery, as they are the ones who guide the care.They are represented in three dimensions: the world, the self, and the others.The desires of the human being remain at the center of the care process (2) .
To be continued The Tidal Model: analysis based on Meleis's perspective Teixeira LA, et al.
Another component of a theory are the presuppositions, which are not subject to testing by the theory itself.Instead, they motivate a set of propositions that are tested and form the basis that determines the view of the theorist.In nursing theories, presuppositions are constituted from nursing, human behavior, life, death, health and disease (1) .
One more component of a theory are the concepts, which are evaluated along the abstract-concrete dimension.The degree of generalization of the concept determines its abstractconcrete level.The greater the generalization of the concept, the more time and geography are transcended, and the greater the level of abstraction.Concepts can also be classified along the variable/non-variable dimension.Non-variable concepts in nursing are: sex, ethnic origin, religion and marital status.Examples of variable concepts (general variables) are: sexual orientation, level of well-being, degree of cultural identification, level of state of the disease (1) .
There are numerous advantages to having general variables.General variables provide more precise classification and allow variations to be more congruent with what actually occurs.Classifying a patient into a man or woman brings some data significance and a certain degree of predictability in the structure and function of biological systems.However, sexual orientation -a general -can help us be more accurate in describing clients and predict their patterns of rehabilitation (1) .As concepts of the Tide Model, the following are listed.

Nursing
Nursing aims to help people access and evaluate their particular experiences in an effort to make them once more writers of the history of their lives, and to begin healing the distress of the past and present as a way to promote human development (2) .

Health
It is the result of the person's autonomy, which occurs through their ability to adapt to every change promoted by the healing environment, even when there is damage.It is also when people maintain their regular daily activities, being aware of themselves and how they deal with it, understanding that pain, illness and death are fundamental parts of life.Thus, nurses must know the personal and social aspects of the individual, as well as how they define health and illness (2) .

Nurse-patient interaction
The Tidal Model assumes that the care process is best characterized as "to care for", which incorporates both the need for "to care about" and "to care for" the person.The collaborative nature of "to care for" produces changes both for the professional and for the person (2) .
Environment It is the context in which people live their vast experiences and nurses create a space for growth and development.
One should consider the person-environment relation, which should be understood as a whole and not just as each of its parts.It is the place where the nurse motivates the patient to see that the environment is safe, through a dynamic relationship (2) .

Nursing problems
The events of life that motivate the person to contact the services, which are seen as opportunities.These events are the natural signs that "something needs to be done".If you respond appropriately, this can be seen as an opportunity for change, a chance to take a new turn in life.These critical events are similar to checking the map or redefining the compass: necessary answers to the ups and downs of the journey of life (2) .

Nursing care
The initial goal is to identify "what needs to be done" and all care is focused on ways to involve the person (and eventually others) in meeting that need.By focusing on what is absolutely necessary, the care plan becomes simpler and more elegant (2) .

Chart 2 -Presuppositions
Nursing It is interactive, developed, a human activity more concerned with the future development of the person than with the origins or causes of his present suffering (3) .

Human behavior
The experience of mental suffering, associated with mental illness or psychiatric disorder, is represented by disturbances of public behavior, or reports of private events known only to the individual in question (3) .

Life
As the tide metaphor suggests, the journey transversed by people endures throughout their lives.This is similar to a trip to the sea.When individuals talk about their personal development stages, or the stages through which they have to go through life, this is similar to sailing from one port to another, or from one continent to another.The nature of the journey of life -large or small -determines the changes in human experience (3) .

Death
Careful exploration of the suicide story is within the "care development" aspect of the Tidal Model.The responsibility is to enable a dialogue with the suicide; one who can begin to address the deep emotional insecurities that make him or her likely to commit suicide.This dialogue is the means for the emotional rescue that forms the interpersonal basis for the implementation of the security plan.In the case of a death wish, the professional's responsibility is to help the person feel emotionally safer by offering to talk about what is important in their life (3) .

Health
The main focus is on engaging with the real world of experience.This approach is characteristic of the nursing focus in the experience and relationship with health and disease, rather than health and disease per se (3) .

Disease
The experience of psychiatric disorder is translated into a variety of disorders experienced each day; the practice of therapeutic nursing is located exclusively within the context of everyday life (3) .
The Tidal Model: analysis based on Meleis's perspective Teixeira LA, et al.
Another component of a theory are propositions, that is, descriptive statements of the properties and dimensions of the concept or the description of the union of two or more concepts together.Propositions promote theory with the power of description, explanation or prediction.If the theory has more presuppositions than propositions it is a theory with limited power.This indicates the existence of some degree of conditions for some descriptions or predictions.In considering the relationship between presuppositions and propositions in the form of relation, rather than relationship (with the number of propositions being greater than the number of presuppositions), this will allow a greater power of explanation (1) .The propositions of the Tidal Model are detailed below.

Nurse
The professional often acts more like a lifeguard, who, realizing that the person is drowning, organizes a rescue.However, the lifeguard does not restrict or dominate the person.Invariably, the lifeguard, "along with" the writhing movements of the drowning person, gradually diminishes them to help him or her swim or float alongside the savior on the trip to the beach.It is the life-guard who helps you build a personal security plan.It is necessary to evaluate and, if needed, frequently revise this plan (3) .
Patient/person People are defined, above all, by their experience.Consequently, the main focus involves developing the necessary conditions to identify and analyze in depth the patient's experience.Through this process, one obtains the appreciation of the human needs of the individual and what needs to be done to identify them (3) .

Nurse-patient relationship
The caregiver and the patient in care are involved in creating a highly specific version of the life narrative.This will include the identification that the person believes to be necessary at that time in terms of support; and it holds the promise of what "needs to happen" to meet that need.As it is believed that, as a result, the simple act of speaking about the experience can change "who" and "what" we are (3) .

Life
It is a journey in an ocean of experience.All human development, including the experience of sickness and health, involves discoveries made in a journey through this ocean of experience (3) .

Mental disorder
At critical points in the person's life journey, one can experience storms or even piracy (crisis).At other times, the ship may begin to submerge and it may face the prospect of drowning or sinking (disintegration).People who suffer from life crises are (metaphorically) in water and risk of deep drowning, or they may feel as if they have been thrown to the rocks (3) .

Nursing problems
The patient affected by a severe and disabling form of mental illness experiences what the layman calls "mental collapse."In the metaphor, such people experience a psychic wreck, and if the proper kind of rescue and recovery does not come soon enough, the person will begin to feel like a psychiatric castaway (3) .

History of life
On a personal level, history is the theater of experience within which reflection and discussion evolve into a permanent form of text editing.The caring process begins and ends here, as all people express the need to develop a coherent account of what has happened and is happening to them in the light of their individual experience.This story is more significant when framed in the patient's vernacular, illustrated by the metaphorical language extracted from its history and the social and cultural environment of the patient's daily life (3) .
Nursing care They use the person's journey experience and its associated meanings to chart the "next step" to be taken on the journey of life.The core evaluation material is entirely written in their own voice.The caregiver's goal is to help people make choices that will guide them based on their current life problems so they can begin to chart a "home" course in their ocean of experience.They emphasize the virtues of giving "the conditions that will be necessary for the promotion of growth and development, rather than instituting care" (3) .

Social inclusion
It highlights the effect of family and friends' permission in empowering the individual to take charge of their lives by grasping (metaphorically) the helm of their experience and starting to chart the course home.In this sense, these emerging findings suggest that reverence for the storyteller is the oldest and most enduring form of empowerment (3) .

Rehabilitation/ recovery
The person may need to be guided to a safe haven to perform repairs, or to recover from trauma (rehabilitation).The ship is new only once, but if the person has recovered the necessary parts from their ship, they may set sail again, in order to put it back into the course of life (recovery) (3) .

Chart 4 -Propositions of the Tidal Model
Valuing the voice The subject's history is the beginning and the end of any care meeting.This history covers not only the share of suffering, but also the hope for its resolution.This is the voice of experience.You should guard it well; it is the voice that begins to help the person rebuild (4) .

Respect the language
The person develops a unique way of expressing their life history, of representing to others what only they know.The language of history, with its unusual grammar and personal metaphors, is the ideal way to illuminate the way (4) .

Develop genuine curiosity
The person is the writer of his life history, but that does not mean that this history is an "open book."It is necessary to develop ways of expressing genuine interest in the person's history as it is written, because it continues to be written.In this way, it will be possible to better understand the storyteller (4) .

Become the apprentice
Each individual is the primary expert in his or her life history.One may begin to learn something from the force of this history, but this will only happen by applying oneself diligently and respectfully to the task by becoming the apprentice (4) .
To be continued The Tidal Model: analysis based on Meleis's perspective Teixeira LA, et al.

Reveal personal wisdom
One has developed a powerful storehouse of wisdom in writing life history.One of the key tasks for the professional is to help reveal this wisdom, which will be used to support the individual and guide the journey of appreciation and recovery (4) .

Be transparent
Both the patient and the professional view the opportunity to become a team.If this relationship thrives, both must be willing to trust each other.The professional is in a privileged position and should model this reinforcement of confidence.It is up to the professional to be transparent at all times, helping the person to understand what is being done and why (4) .

Use the available toolkit
The personal history contains countless examples of "what worked" or "what might work" for that person.These represent the main tools to be used to unlock or construct the recovery history (4) .
Ability to take a step further The professional and the person work together to build an appreciation of what needs to be done "now."The first step is crucial and reveals the power of change that points to the ultimate goal of recovery (4) .

Give the gift of time
There is nothing more valuable than the time the practitioner and the patient spend together.Time is the midwife of change.There is no merit in asking "How long do we have?".We have all the time we need.The question is certainly "how can we use this time?" (4).

Experience constant change
Change is inevitable because it is constant.This is the story common to all.The professional task is to develop awareness of how this change is happening and how this knowledge can be used to guide the person to stay out of danger or distress, returning to the course of appreciation and recovery (4) .Some questions should be observed to help determine the concept of clarity, such as: are the concepts defined operationally?Do they appear to have content and construct validity?The propositional clarity is manifested in a coherent and logical presence of propositions and systematic connections between the concepts of the theory.In addition, the clarity criteria vary, ranging from high to low clarities (1) .
The predominant psychiatric perspective over a long period is based on the power to solve, repair or otherwise correct the problems of life, called "mental illness".In general, belief in psychiatric medicines -often used only to alleviate instead of curing -remains.Likewise, the expectation that some magic exists in the various "spoken" cures seems stronger than ever.However, while there may be "magic", it cannot be denied that traditionally people have been encouraged to believe in this cure (3) .
As aforementioned, the Tidal Model incorporated concepts about the therapeutic use of "self" in the development of several roles and functions required in the nursing practice of Peplau (1952), Travelbee (1969) and Forchuk et al. (1998).It also incorporated the potential value of interpreting mental health problems, such as living problems of Sullivan (1953)  and Szasz (1961) (5) .
The theory began to articulate human values in the process of care, recognizing the rational nature and complexity of human experience.This recognition goes beyond quantification, which is observable and knowable, and such values are later considered by the nurse through the inexpressible elements in the nurse-patient relationship.
The structural complexity of nursing is in the social and human natures, in the dialogue, in the mutual interaction between the nurse and the patient, that takes place in a change in the processes of life and human development, as a way of understanding and particular definition of life, health, illness and death.
As a reciprocal process, the nurse-patient relationship happens in verbal and non-verbal communication, in affection, in empathy with the other, in the interaction involving the participants' contexts.This process is perceived and interpreted in a meeting, being "with" the patient to develop care and not "for" nursing practice (6) .
The Tidal Model is based on the inherent value of each individual and their potential to change, as well as the capacity for autonomy in health production, with the understanding that people are able to supply their own basic physical needs (6) .
Often the nurse uses her or his theoretical support and her life-time experiences to increase the capacity for intervention in solving the person's problems, with the sensitivity in the understanding that people differ in their ability to deal with the situations they have experienced.The nurse must allow the development of interpersonal skills to provide holistic and integral attention, facing the problems through intimacy as a way to provide immediate relief, guaranteeing active listening and the authentic presence of the professional (3) .
The Tidal Model is structured with well-established and logically appropriate concepts, with broad ideas of the situations lived by the person and with a process of practical application based on scientific data and theories of mental health and psychiatry (6) .
This theory prioritizes the clarity of the concepts through the practical operationalization of the person's language; therefore, this language is not modified to a professional language, which is incomprehensible.In this sense, it can contribute to the orientation of nurses' goals, to meeting human needs, knowing them and knowing that they are the person's, not the professional's.
The tide metaphor intertwines with and facilitates the understanding of ideas, premises, concepts, and relationships as a way of helping everyone through everyday language in the metaphoric ocean of experiences.It can be applied and adapted to different cultures and populations, as it does not require definition of age or gender, and can be installed in various types of patient care services, from primary care services to specialized centers and hospital units.
In addition, the nursing practice occurs through the ten commitments that represent the existence or not of the philosophical foundation of the Tidal Model.These commitments Chart 4 (concluded)  have fostered consistency in care and allow for systematic connections of the concepts and presuppositions of the theory.
It is not easy to determine the boundaries between clarity and consistency.Both the degree of congruence and the fit between the different components of the theory are described in the consistency.Thus, the fit between conceptual presuppositions and definitions, between defined concepts and the use of propositions, and through clinical concepts and examples, it can be determinant of consistency (1) .
The vital problems of the person and nursing are based on a systematic investigation that generated the theory.In this context, the Tidal Model goes from a philosophical perspective to a worldview and personal beliefs in the production of care.Therefore, theory is not only centered on seeing, but also on knowing, through clinical observation, practice, research, and philosophy.
As observed, the life histories elaborated based on the meetings between nurse and patient are obtained by the patient's description, as the nurse is oriented to maintain the spirit of stimulation of the person in search of resources of strengthening and healing.These resources are obtained through change strategies built alongside the care plan, highlighting the resources of each person and emphasizing that the change is the only constant (7) .
Introduced in nursing care in acute care, the Tidal Model possibilitated the implementation of a concept of continuous care, with emphasis on the needs of the person in three different forms of care: critical, transitional and development.The concept of continuous care ranges from the hospital to the community; the main focus of care is the person's needs, rather than how this need arises (5) .
Recognized as an important intermediate nursing theory, this theory is practiced by a range of courses across the spectrum of mental health care, being adopted by more than 100 projects in countries such as Australia, Canada, England, Ireland, Japan, New Zealand, Scotland and Wales.It includes young people with acute psychiatric problems, rehabilitation, autistic, with learning disabilities, as well as services of care for the elderly, through the division of hospital care in the community (5) .
A successful example of the diversity of scenarios to use theory is that of the New Zealand mental health program, which applied it to the Maori Indians.In this way, it avoids the impression that the presuppositions are characteristic of Western psychiatric culture (5) .

FINAL CONSIDERATION
The clarity of the theory was verified through the demonstration of the functional components, presuppositions, concepts and propositions.The practical operationalization of the language of the individual, through the recognition of their language, emerges as a contribution in the orientation of the nurses' objectives and it favors the attendance of human needs by identifying them, knowing that they are the person's, not the professional's.
Consistency is due to the possibility of application in several contexts, especially by scientific attestation in several countries with different populations, highlighting the theory as a theoretical base in the whole field of mental health.
As the theory has not yet been translated into Portuguese, only two articles in this language address its concepts.Both demonstrate a vast field of possibilities for research and application in the clinical practice of Brazilian nursing in order to support care.