MODELS OF HEALTH
Biomedical	Psychological	Sociological
Pathogens Genetics Biochemical Hormonal Injury Environment	Thoughts Feelings Behaviours Unconscious drives Learning Environment	Social Cultural Ethnicity Economics Politics Environment

Additionally, health can be examined both objectively and subjectively. Objective measures such as an X-ray or scan can indicate health or illness, while an individual’s subjective interpretation will report whether he or she feels healthy or ill – but there may be no correlation between the two. For example, a person may report feeing healthy but have dangerously high blood pressure, or another person may report pain for which physical pathology cannot be identified. Therefore, given the range of criteria and the different perceptions that can influence a definition of health, it is not surprising that many interpretations exist and that debate surrounds an agreed definition of the concept (Australian Institute of Health and Welfare (AIHW) 2007, Jormfeldt et al 2007).

Furthermore, health can have different meanings for the general public or lay people than it does for health professionals. Three consistent themes arise in research into lay people’s understanding of the concept of health. They are: health is not being ill; health is a prerequisite for life’s functions; and health involves both physical and mental wellbeing (Baum 2008 p 7). Baum suggests that these lay definitions have more in common with the World Health Organization’s (WHO) definition of health than biomedical interpretations do.

Biomedical model

Throughout history, explanations for illness have included somatic disequilibrium, demonology, witchcraft and environmental pathogens. In Western-industrialised countries up until the middle of the 20th century, health was generally viewed as the absence of disease and illness was seen as a pathological state. With the emergence of the public health movement in the 19th century the biomedical approach (also called the medical model) rose to prominence and dominated Western medicine for over 200 years. The biomedical model proposes organic, pathological theories to explain and treat illness. Essentially, this approach is an illness-based model with the underpinning assumption that illness and disease are caused by disequilibrium in the body that is brought about by one or more of the following:

• biological pathogens such as viral or bacterial infection

• trauma or injury such as acquired brain injury

• a biochemical imbalance in the body such as hypothyroidism, diabetes

• degenerative processes such as arthritis or dementia.

From the 19th century, public health strategies utilising a biomedical approach such as mass vaccinations and sanitation have achieved a worldwide reduction in many communicable diseases like polio, smallpox and pneumonia. In the 20th century, the discovery of antibiotics, psychotropic medications and the development of sophisticated surgical techniques such as organ transplantation have enabled previously life-threatening diseases and conditions to be treated and, in many instances, cured.

However, by the latter half of the 20th century it became apparent that the treatment era of the previous decades did not live up to the expectations of the scientific or wider community. In Western countries, for example, diseases related to lifestyle now pose a greater threat to health than that of infectious diseases. Also, with regard to the treatment of infectious diseases, some bacterial strains have developed resistance to antibiotics and for most cancers neither a cure, nor preventive vaccination has been discovered. In the main, cancer prevention and chronic illness management strategies are related to lifestyle and the environment, such as cease cigarette smoking, use sun protection, be physically active, eat a healthy diet and maintain weight within the healthy range.

In the mental illness field the unwanted side effects of antipsychotic drugs are often problematic and can contribute to non-adherence to treatment, for example, the rapid and sustained weight gain and iatrogenic diabetes mellitus experienced by some patients taking atypical antipsychotic medication to treat schizophrenia (Bai et al 2006). Such consequences of treatment present a challenge to both patients and health professionals with regard to the relative cost–benefit of the treatment. For patients, the unwanted social and health consequences may interfere with adherence to the recommended treatment. For the health professional, there is the ethical dilemma of encouraging adherence to a treatment for one health condition such as schizophrenia that carries a high risk that the patient will develop another serious health condition such as diabetes mellitus.

CHALLENGES TO AN EXCLUSIVE BIOMEDICAL APPROACH

Initially, the biomedical model held great promise to improve the health of individuals and communities. Scientific research in the 20th century led to the discovery of medications that could cure, or eliminate, many diseases. Sulphur drugs – developed in the 1930s – and, later, other antibiotics revolutionised the treatment of infection. In the mental health field the first antipsychotic medication (chlorpromazine) was introduced in 1950. At the time it was lauded as a breakthrough in the treatment of schizophrenia because of its ability to reduce disruptive behaviour (Meadows at al 2007). Patients who would have been in straitjackets and lived out their life in a mental institution now were able to be discharged and returned to live in the community.

However, by the middle of the 20th century concerns were mounting regarding the cost escalation of scientific, technological medicine and worldwide there was recognition of the need for sustainable environments. It was also evident, particularly in Western countries, that the diseases that threatened communities were no longer infectious and acute but were chronic and related to lifestyle. For example, the health conditions that now carry the greatest burden of disease are mental illness, cancer, cardiovascular disease, diabetes, substance abuse and interpersonal violence (Marmot & Wilkinson 2006).

Challenges to the biomedical model as the exclusive framework for understanding health and to structure the delivery of healthcare services began to emerge from the middle of the 20th century, the major criticism being that an exclusive biomedical approach fails to take into account the contribution of broader psychological, sociological, political, economic and environmental factors that influence health and illness. A further criticism of an exclusive biomedical approach is that health resources are directed to costly curative services rather than to health promotion or illness prevention. Baum argues that ‘there needs to be more research on the ways in which social and economic factors affect health and what social, educational, housing and health interventions most improve health and health equity’ (Baum 2008 p 145).

The emerging questioning of the dominance of the biomedical model coincided with the establishment of WHO by the United Nations in the 1940s. WHO was given the brief to work towards ‘the attainment by all peoples of the highest possible level of health’ and in 1946 the organisation released its, then groundbreaking, definition of health that stated:

Health is a state of complete physical, mental and social wellbeing and not merely the absence of disease or infirmity.

(WHO 1946)

This definition was developed in response to the changing healthcare needs of populations. The WHO explanation contested the efficacy of the prevailing biomedical view of health at the time by recognising the contribution of social and psychological as well as physical factors to health and illness. Broadening the definition of health by WHO signalled the introduction of what became known as the biopsychosocial approach in which the contribution of individual, lifestyle and social factors to health outcomes is acknowledged. It also laid the foundation for the emergence in the 1970s of the primary health care/new public health movement.

Nevertheless, while the WHO definition of health is a comprehensive one, it has its limitations. The use of the word ‘complete’ is problematic. Is it possible to be completely healthy in all areas identified (physical, emotional and social) and at all times? And if this is not possible does it necessarily follow that an individual who has one health issue is unhealthy? Consider, for example, a person with a well-managed chronic illness (asthma) or a disability (vision impairment) who is otherwise in good health. If you asked either of these two individuals to rate their health do you think they would describe themselves as unhealthy? They probably would not. When asthma is managed by medication and vision impairment corrected by glasses the person does not experience limitations from the health issue. Therefore, in seeking a comprehensive definition of health other factors must be considered including the individual’s sense of control of and satisfaction with his or her health and life.

And finally, while 86% of increased longevity in Western countries can be attributed to the public health initiatives of the 19th and early 20th century (i.e. clean water, suitable housing and sanitation) only 4% of increased longevity can be attributed to sophisticated medical interventions of the 20th century (New Internationalist 2001). Given that up to 75% of governments’ health budgets are allocated to acute hospital services there seems to be a disparity between resource expenditure and health outcomes (Government of South Australia 2003). Hence, the question arises: Is the allocation of the bulk of health funding to acute treatment services the most effective allocation of financial resources to achieve the best health outcomes for individuals and communities?

In summary, the biomedical model holds the view that health outcomes are influenced by physiology, with health occurring when the body is in a state of equilibrium and illness being a consequence of physical pathology or disequilibrium. The approach is limited as a theory to explain and understand health and the provision of healthcare services because it is a one-dimensional model that fails to take into account the complex interplay of other factors, namely, psychological and social factors that interact with biological factors and impact health.

Biopsychosocial model

The philosophy that underpins the biopsychosocial model is that health or illness result from a complex interplay between biological, psychological and social factors. The model emerged in the 1970s in response to realisations regarding the limitations of the biomedical model in a changing world, as previously discussed.

The notion of an alternative to the biomedical model was first proposed by Engel (1977) and quickly gained momentum among health professionals and policymakers. The biopsychosocial model is holistic in approach and thereby avoids the mind–body split inherent in the biomedical model. A further outcome of this approach is the recognition of the contribution made by allied health professionals to healthcare and the emergence of the multidisciplinary team as a mechanism for providing health services.

HEALTH PRIORITIES

Australia’s National Health Priority Areas (Australian Government DH&A 2005) are health issues identified by the federal Department of Health and Ageing for focused attention because they contribute significantly to the burden of illness and injury in Australia. The seven priority areas are: cancer control; injury prevention and control; cardiovascular health; diabetes mellitus; mental health; asthma; and arthritis and musculoskeletal conditions – all of which have complex aetiology including lifestyle, biological, psychological and social factors. In addressing these health problems the holistic nature of the biopsychosocial model offers greater opportunity to improve health outcomes than a biomedical approach alone because the biopsychosocial approach addresses more than just the symptoms of the condition.

Nevertheless, despite the intrinsic appeal of the biopsychosocial model some critics argue that, generally, social issues are not sufficiently addressed in practice (Lyons & Chamberlain 2006 p 12). Utilising another approach – primary health care/new public health that operates from a biopsychosocial framework and has a strong emphasis on social and political issues that impact health – is a way to overcome this shortcoming.

Primary health care/new public health

The emergence of the primary health care/new public health movement also in the 1970s coincided with the growing awareness that psychological and social influences as well as physical and biological factors influenced health outcomes for individuals and communities. It was formally endorsed as a mechanism to achieve Health for all by the year 2000 at the 1978 WHO conference in the Declaration of Alma-Ata in the former Soviet Union. The declaration was the culmination of a WHO–UNICEF sponsored conference at which representatives from 134 nations endorsed the declaration with the philosophical principles of: social justice; equity; access; empowerment; self-determination; political action; health promotion and illness prevention; collaboration between consumers, practitioners, countries, governments and those responsible for health; and striving for world peace.

Worldwide policymakers, health professionals and communities were increasingly looking beyond the biomedical model for answers to health problems (Baum 2005). In 1981 LaLonde, the Canadian Minister of National Health and Welfare, described four general determinants of health that he called human biology, environment, lifestyle and healthcare organisation. Supporting a shift from a biomedical approach to a broader approach acknowledging biopsychosocial factors Lalonde stated:

There can be no doubt that the traditional view of equating the level of health in Canada with the availability of physicians and hospitals is inadequate. Marvellous though health care services are in Canada in comparison with many other countries, there is little doubt that future improvements in the level of health of Canadians lie mainly in improving the environment, moderating self imposed risks and adding to our knowledge of human biology.

(Lalonde 1981 p 18)

In 1986, eight years after the Alma-Ata declaration, the first WHO International Conference on Health Promotion was held in Ottawa, Canada. Conference participants developed an action framework of five strategies (the Ottawa Charter) to achieve Health for All. These five strategies have become the cornerstone of the primary health care/new public health movement.

Table 4.2 Actions of the Ottawa Charter for Health Promotion

OTTAWA CHARTER STRATEGY	ACTION
Build healthy public policy	Direct policymakers to be aware of the health consequences of their decisions and to develop socially responsible policy
Create supportive environments	Generate living and working conditions that are safe, stimulating, satisfying and enjoyable
Strengthen community action	Empower communities, enable ownership and control of their own endeavours and destinies
Develop personal skills	Support personal and social development through providing information, education for health and enhancing life skills
Reorient health services	Share responsibility for health promotion in health services amongst individuals, community groups, health professionals health service institutions and government

Health of Australians and New Zealanders

When compared with other countries in the world, the health of Australians and New Zealanders ranks highly. It is rated among the top 10 developed countries in the world across a range of significant indicators. Life expectancy is ranked among that of the top nations in the world. See Table 4.3 for life expectancies for selected countries.

Table 4.3 Life expectancy in selected countries

SELECTED COUNTRIES	LIFE EXPECTANCY AT BIRTH
Singapore	81.71
Hong Kong	81.59
Japan	81.25
Australia	80.5
Indigenous Australians	62.0
Norway	79.54
New Zealand	78.81
Māori	71.1
United Kingdom	78.54
United States	77.85
China	72.58
Indonesia	69.87
Papua New Guinea	65.28
India	64.71
Botswana	33.74