Concept of quality of life in health care research: a review

International Journal of Community Medicine and Public Health Kaur M et al. Int J Community Med Public Health. 2023 Oct;10(10):3931-3937 http://www.ijcmph.com pISSN 2394-6032 | eISSN 2394-6040

DOI: https://dx.doi.org/10.18203/2394-6040.ijcmph20232869

Review Article

Concept of quality of life in health care research: a review

Mandeep Kaur1,2, Sukhpal Kaur2*

1National Consortium for Ph.D. in Nursing by Indian Nursing Council in collaboration with RGUHS, India 2National Institute of Nursing Education, PGIMER, Chandigarh, India Received: 03 September 2023 Accepted: 18 September 2023 *Correspondence: Dr. Sukhpal Kaur, E-mail: Sukhpal.trehan@yahoo.in Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

ABSTRACT Quality of life (QoL) is the most studied concept in health care research. With an increase in life expectancy and consequently with more prevalence of chronic diseases, the QOL needs to be paid attention. It is a multifactorial concept and many tools are adopted to study QOL. The present article analyses the concept of QOL in the context of healthcare research. Articles for this were searched from PubMed, CINAHAL, Cochran and EBSCO. A detailed review of QoL in health care research including its components, models and various tools being used with their application are discussed in the current article. Keywords: Health status, QoL, QoL models, WHO, WHO QOL -100

INTRODUCTION

Traditionally common indicators used for evaluating the state of the population health were life expectancy and the cause of death. But with an increase in life expectancy, there was a felt need to find out such measures for health which can reflect the quality of all the years lived.1 The term QoL was first used in the form of a keyword in the medical literature databases in 1975.2 Initially the socio- psychological aspect of QoL and its determinants were identified. During the last decade of the 20th century, researchers started focussing on the assessment of subjective aspects of QoL of individuals.3 Few years later, the World Health Organization affirmed that there is a need for evaluate and enhance people’s QoL.1 Since then it has been widely used for the evaluation of individual’s feeling about his/her well - being focusing on various favourable and adverse conditions of life. An individual’s feelings about their own life are given prime consideration in measurement. QoL has different meanings to different people and as per area of application. The term health-related QoL (HRQoL) is more commonly used in health care research to remove any ambiguity in the definition of QoL.

In 1980s, term ‘HRQoL’ was first introduced in published medical literature. It includes all those aspects related to QoL which relates to health. However, in literature both terms i.e., QoL/ HRQoL are often used interchangeably, but these two are distinct concepts. QoL is reflected as overall satisfaction of person with his /her life, which may be evaluated as single concept or can be split into various domains. Whereas HRQoL as a specific concept includes all aspects of health and is evaluated domain- wise. So, it can be considered “an individual’s subjective assessment of his QoL in relation to physical, psychological and social domains of health.”4 However WHO has used and defined term QoL to be used in field of health care.1 Some definitions even fail to make distinction between HRQoL, QoL and health. Various questionnaires claiming to measure HRQoL are actually measuring individual’s health status as perceived by him/her. So, concept of HRQoL is perplexing. Proposed solution is defining HRQoL as way health is being empirically estimated as affecting QoL.5 QoL relates to overall definition of health, which includes individual's perception of his own life, focussing on all human life dimensions.6 In traditionally used HRQoL utility measures more weightage is given to physical domains,

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however it is important that while defining itmental and social domains should be equally emphasized.7,8

Definition of QoL

WHO has defined QoL as “an individual's perception of their position in life in context of culture and value systems in which they live and in relation to their goals, expectations, standards and concerns. It is broad-ranging concept affected in complex way by person's physical health, psychological state, personal beliefs, social relationships and their relationship to salient features of their environment.”1

Rice (1984) defined QoL “as a degree to which the experience of an individual's life satisfies that individual's wants and needs (both physical and psychological). Much of the debate about how QoL should be defined has centered around subjective versus objective approaches. Rice further defines objective QoL (OQoL) as degree to which specified standards of living are met by objectively verifiable conditions, activities, and activity consequences of an individual's life and subjective QoL (SQoL) as set of affective beliefs directed toward one's life.”9

Another definition was “measure of difference between hopes and expectations of individual and individual’s present experience. HRQoL is primarily concerned with those factors which fall within spheres of influence of health care providers and health care systems.”10

HRQoL

Since health is considered multidimensional concept, the HRQoL also incorporates all domains of physical, mental, emotional, and social functioning.7 HRQoL is dependent on one’s health status and it focuses on the consequences of one’s health status on QoL. Centre for disease control has defined HRQoL as “an individual’s/group’s perceived physical and mental health over time”11 Table 1 highlights because it is pertinent to measure QoL in health care.

Table 1: Measuring QoL in health care research.4,11

DOMAINS OF QoL

WHO has divided QoL into four broad domains and 24 facets in total under these domains as discussed below

Physical health: This domain includes facets associated with physical health and includes energy, pain, discomfort, sleep, rest, etc.

Psychological: This domain incorporates psychological aspects of health and QoL. Its facets are based on bodily image, negative and positive feelings, self-esteem, thinking, memory and concentration.

Independence level: It takes into consideration how independent a person is in his/her life. Facets of this domain consider mobility, ability to perform daily living activities, capacity to work and dependence on medicinal assistance.

Social relations: It includes the facets related to social as well as personal relationships. Environment: This domain takes into account the environmental component of QoL. It includes the availability of financial resources, access to health care, the environment of home, opportunities to learn new skills and recreational opportunities etc.

Spirituality/religion/personal beliefs: This domain has a single facet assessing religion/ spirituality/ personal beliefs.12

DETERMINANTS OF QoL

QoL is determined by a number of factors, which include physical health conditions, mental well-being, social conditions etc. Kivits et al performed secondary analysis of epidemiological data of HRQoL from 2 national surveys and revealed that the important determinants of QoL are main social indicators like living as couple, educational status, occupation and income per household, independent of age and gender.13 Singh et al conducted a study to assess HRQoL among representative populations of South Asia.14 This study revealed that HRQoL was significantly associated with age, gender, education, income, and employment status. In a study of Jordanian population by Matalqah et al it has been revealed that many physical and emotional factors like age, presence of chronic disease, and stress due to lower socioeconomic status were affecting HRQoL.15 QoL also varies as per disease status as review conducted by Basavaraj et al has revealed that physical symptoms, drug therapy, psychological state of health, social support, using coping-strategies, level of spiritual wellness, and presence of psychiatric illness are important predictors of QOL in PLHIV.16 Similarly a study by Cho et al stated that HRQoL in patients with chronic hepatitis C is linked with age, gender, educational status, living type, employment, monthly income and presence co-morbidity.17

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TOOLS TO ASSESS QoL

There are various ways to assess HRQoL. This can be measured by using subjective measures as well as objective assessment tools. Selective tools may be required for the assessment of the QoL in different populations or different disease states. HRQoL measures can establish the range of problems that affect patients,

these can help to identify any ongoing problems that might get ignored otherwise. These can also be a predictor of treatment outcomes. HRQoL measures can help to calculate quality adjusted life years by combining them with measures of time in a particular health state. These measures of HRQoL can be classified as generic, disease-based tools and population-specific tools for measuring HRQoL (Table 2).18

Table 2: Commonly used QoL instruments.

Continued.

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MODELS OF HRQoL

Various models of QoL have been proposed. However, this paper restricts to the commonest ones.

Ferran and colleagues’ QoL model and QoL index

This model assumes that QoL is an individualistic phenomenon and is dependent on the uniqueness of the experience of life for every person. This model defines QoL “as satisfaction with the aspects of life that are important to the individual.” The QoL is divided into four domains including health, functioning, psycho- spiritual, socio-economic, and family domains. The “Ferrans and powers QoL index” was developed based on this model.45

Centre for health promotion model

This model was created by Dennis et al at the University of Toronto. This refers to the QoL in the context of disease. This model is based on WHO’s definition of the QoL. QoL as per this model is defined as “the degree to

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which a person enjoys the important possibilities of his or her life”. This model has divided QoL into three subdomains including being, belonging and becoming. Importance and enjoyment are two important factors in determining QoL. So QoL is “relative importance attached to each particular dimension and the extent to which a person enjoys with respect to each dimension”. 46

World health organization international classification of functioning disability and health (WHO ICF)

This model provides a description of health and its states and gives a common language suitable to be used across disciplines and cultures. The WHO ICF model has been divided into two parts. The first part takes into account the functioning and disability and the second part addresses many contextual factors like environmental and personal. However, the WHO ICF is not specific to HRQoL, rather it provides a base for mapping and classification rather than as a guide for the generation of hypotheses in the field of HRQoL.47

Bakas et al have concluded that Ferran and colleagues’ model which is a revised version of Wilson and Cleary model can play a very important role in guiding the HRQoL research and practice.42,44,45,47 Frequent use of this model will provide aid in testing further refinement and evidence about association among HRQoL concepts, which are common across different populations. Using the same model will also help in comparing HRQoL across various populations and advance the knowledge base in the field of HRQoL.

THE GREY ZONE AND WAY FORWARD

No matter how much attempt is made to assess the QoL but this concept can never be fully captured as it is a highly individualistic concept and has different meanings for different people. Whenever the concept of QoL is used in health care, its aim is to have a patient-centred approach rather than a disease - centred approach. But only QoL is not a sufficient measure to assess patient outcome. In literature overlapping use of the term QoL and HRQoL cause confusion over the meaning and distinction of these two terms. So, the assessment of the QoL should act as an adjunct not as a substitute to assess patient-centred outcomes Multidisciplinary approach should be adopted while assessing QoL. Reliance should not only be made upon the assessment tool but effective communication techniques and effective relationships should be established with the patient in order to get in- depth insight into the patient’s QoL. As the QoL is an individual concept, strategies to improve it should also be individual and designed in such a way that these get customized as per individual patients’ needs.

CONCLUSION

QoL is an important concept in the field of health care. It has different determinants as per the disease condition of

the patient. Assessment of QoL will help to improve the health status of patients and the quality of care provided. However, the researchers need to be careful while choosing the appropriate measure of QoL as per the need of the group to be studied.

Funding: No funding sources Conflict of interest: None declared Ethical approval: Not required

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