Introduction & Importance of Theories in Public Health

Definitions of Terms

Public Health

  • Defined as “the science and art of preventing disease, prolonging life and promoting health through organized efforts and informed choices of society, organizations, public and private, communities and individuals.”
  • Concerned with threats to health based on population-level analysis rather than solely on individual cases.
  • Populations of concern can range from a handful of people to entire continents (e.g., during a pandemic).
  • Health is multidimensional, echoing the WHO\,1948 description of “a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.”

The Holistic Nature of Health

  1. Physical Health – Body‐related well-being (fitness, absence of illness).
  2. Mental Health – Positive sense of purpose and belief in one’s worth (feeling able to cope).
  3. Social Health – Perception of support from family/friends (someone to talk to, group activities).
  4. Emotional Health – Capacity to express feelings and form/maintain relationships (feeling loved).
  5. Spiritual Health – Ability to integrate moral or religious principles into life practices.
  6. Sexual Health – Acceptance of one’s sexuality and ability to express it satisfactorily.
  • Holistic health therefore addresses the total well-being of the individual.

Social Science

  • Academic disciplines that study the social life of human groups and individuals.
  • Investigate institutions, interpersonal relationships, and human society’s functioning.
  • Branches include:
    • Psychology – Scientific study of human behaviour & mental processes.
    • Sociology – Behaviour of humans in groups; explores group development, mores (formal rules) & folkways (informal customs).
    • Anthropology – Study of behaviour within culture; focuses on knowledge, beliefs, values, customs, language, symbols.

Public Health Practice & Interventions

  • Aims to improve health & quality of life via prevention and treatment of physical and mental conditions.
  • Tools include surveillance of cases/indicators and promotion of healthy behaviours.
  • Iconic measures: hand-washing promotion, breastfeeding campaigns, vaccination delivery, condom distribution to reduce STIs.
  • Public Health is thus the art and science of promoting population health by nurturing healthy people, places, and policies.

Medical Sociology

  • Studies social causes and consequences of health and illness.
  • Analyses society insofar as it concerns health & disease.
  • Core research foci:
    • Social patterns of disease.
    • Interaction between health personnel & patients.
    • Social functions of health organisations.
    • Interrelationship between health-care systems and other social systems.
  • Emphasises that health is shaped critically by social factors.

Key Sociological Concepts for Public Health

  • Society, not the isolated individual, is primary unit of analysis.
  • Collective-level units: family, group, neighbourhood, city, organisation, state, globe.
  • Interests: maintenance/change of the social fabric (structure), conflict & resolution processes, creation/sustainment of systems (e.g. a nation’s health-care system).

Anthropology & Medical Anthropology

  • Explores culture’s role in human behaviour, life-patterns, systems of knowledge, belief, language, and symbol.
  • Investigates: cultural beliefs, attitudes, roles, gender norms, language, symbolic expression, social authority & legitimacy, health knowledge systems, healing practices, healers.
  • Medical anthropology pursues a biocultural synthesis: merging biological and cultural analyses of health, illness, death (e.g., diarrhoeal infant mortality).

Theories: Definitions & Relevance

  • Theory: systematic set of interrelated concepts, definitions, and propositions explaining or predicting events/behaviours by specifying variable relations (Kerlinger).
  • Model: drawing upon multiple theories to illuminate a specific problem in a defined context (Glanz et al.).
  • Successful programmes rest on understanding health behaviours and their context; thus theories guide intervention design.
  • Applying theories requires a blend of methods and strategies from social & health sciences – collectively termed Social and Behavioural Science Theories.

Why Use Theory?

  1. Explain why people engage (or not) in health-promoting behaviours.
  2. Identify information needed to craft effective interventions.
  3. Provide insight on how to structure a programme for success.
  4. Suggest mechanisms to influence and change behaviour.

Categories of Theory

  1. Explanatory Theories – Illuminate reasons for behaviours/events.
  2. Change Theories – Map backwards from long-term goals (Theory of Change) to required preconditions, guiding planning, participation, and evaluation for social change.
  • They are complementary: explaining why (e.g., employee smoking) plus guiding how to change (cessation strategy).
  • Most theories/models contain both elements, though some emphasise one.
    • Health Belief Model (HBM) – primarily explanatory.
    • Stages of Change (Transtheoretical Model, TTM) – originally designed for change guidance.

Theories & Social Determinants of Health

  • Both theory types are anchored in understanding how social, cultural, and economic factors drive behaviour formation, maintenance, and change.
  • Modern consensus: interventions must embrace an ecological perspective (upstream approach).
    • Target not only individuals but also interpersonal, organisational, and environmental layers influencing behaviour.

Core Theoretical Models in Health Behaviour

  1. Health Belief Model (HBM) – Addresses perceived susceptibility, severity, benefits, barriers, cues to action, self-efficacy.
  2. Transtheoretical Model / Stages of Change (TTM) – Progression through pre-contemplation, contemplation, preparation, action, maintenance (and sometimes termination).
  3. Social Cognitive Theory (SCT) – Reciprocal determinism between personal factors, behaviour, and environment; key constructs: observational learning, outcome expectations, self-efficacy, reinforcement.
  4. Theory of Reasoned Action (TRA) / Theory of Planned Behaviour (TPB) – Intention as immediate antecedent of behaviour; influenced by attitudes toward the act, subjective norms, and perceived behavioural control.
  5. Social Ecological Model (SEM) – Multiple nested levels (individual, interpersonal, organisational, community, policy) affecting health.

Individual (Intrapersonal) Level Considerations

  • The individual is the basic unit of health-promotion practice; aggregates compose groups, organisations, communities, nations.
  • Health professionals often engage in one-on-one counselling, patient education, producing educational materials; thus competence in individual-level theory is essential.
  • Intrapersonal factors:
    • Knowledge – factual information and comprehension.
    • Attitudes – feelings/opinions toward an object, person, or behaviour.
    • Beliefs – perceptions of truth/falsity.
    • (Implied) Skills, self-efficacy, perceived risk, etc.

Practical Implications & Examples

  • Hand-washing campaigns can be mapped onto HBM constructs (perceived susceptibility to infection, benefits of cleanliness, cues such as posters).
  • Smoking cessation may employ TTM to segment employees by readiness and tailor interventions (e.g., motivational interviewing for contemplation stage).
  • Condom distribution integrates TPB factors (attitudes about condoms, peer norms, perceived control over obtaining/using them).
  • Breast-feeding promotion uses SCT (observational learning via peer counsellors, enhancing self-efficacy, modelling).
  • Diarrhoeal infant mortality analysis through medical anthropology highlights cultural feeding practices alongside biological pathogen exposure – demonstrating biocultural synthesis.

Ethical, Philosophical & Upstream Considerations

  • Public Health’s ecological perspective urges ethical focus on equity: addressing social determinants, not blaming individuals.
  • Theories must be applied with cultural sensitivity (anthropological lens) and awareness of power dynamics (sociological lens).
  • Interventions that change environments (policy, organisational norms) honour the principle of structural prevention and minimise victim-blaming.

Numerical & Statistical References (Explicit)

  • Year of holistic WHO definition: 1948.
  • Theory application often involves measuring constructs (e.g., self-efficacy scored 1{-}5 Likert scales, incidence rates per 100{,}000 population, etc.) though explicit figures were not supplied in the transcript.

Conclusion

  • Understanding and skilfully applying social and behavioural science theories is crucial for effective public-health interventions.
  • Theories provide explanatory lenses and roadmaps for change, reinforcing an ecological, multidisciplinary approach that spans individual to policy levels.
  • Mastery of concepts from sociology, psychology, anthropology, and allied disciplines enables practitioners to design, implement, and evaluate programmes that authentically improve population health and quality of life.