The determinants of health, and how they interact to produce inequities

The syllabus names five groups of determinants. Learning them as a list is enough for one mark; learning them as a sequence is what earns the rest, because they are not five parallel influences. They act in an order, from the conditions of society down to the state of a body.

• Broad features of society — culture, social inclusion, the education system, employment structures, law and media. The furthest upstream, and the hardest to see because they are the water everyone swims in.
• Environmental factors — housing quality, air and water, location, transport, whether there is anywhere safe to walk. Largely set by the level above.
• Socioeconomic characteristics — income, education, occupation. This group has the strongest and most consistent relationship with health of any in the list.
• Health behaviours — diet, activity, smoking, alcohol, help-seeking. Usually treated as the beginning of the story; they are much closer to the middle.
• Biomedical factors — blood pressure, weight, cholesterol, genetics, birthweight. The furthest downstream, and the ones a clinic can actually measure.

The words upstream and downstream capture the relationship. A clinic treats blood pressure, which is downstream. The reasons that population has higher blood pressure — work, stress, food environment, housing, income — are upstream. Treating downstream helps the individual in front of you; changing upstream is what moves a population.

The syllabus asks directly: how do the determinants interact to affect the health of population groups? Three kinds of interaction cover almost every case you will meet.

• Chains. One determinant produces the next. Lower education leads to lower-paid and less secure work, which leads to poorer housing in a cheaper area, which leads to worse air quality and further distance from services, which produces worse health outcomes. Each link is ordinary; the chain is the effect.
• Clustering. Disadvantages arrive together rather than singly. A household with low income is more likely to also face insecure housing, unsafe work, poor transport and limited local food choice. Because they cluster, their effects multiply rather than add — and this is why a single-issue intervention so often disappoints.
• Feedback. Poor health causes disadvantage in return. Illness reduces the ability to work, which reduces income, which worsens the conditions that produced the illness. This is the loop from Lesson 2, running at the level of a life rather than a fortnight.

The result across a population is the social gradient in health: health improves at every step up the socioeconomic ladder, not merely at the bottom. That detail matters more than it looks. If only the poorest were affected you could treat it as a problem of poverty; a gradient running the whole way up says the distribution of resources and control across the whole society is doing the work.

The syllabus asks: what are the sociological causes of risky health behaviours? The word sociological is doing the work. It rules out the answer most people reach for — that some individuals are less careful or less informed — and asks instead what it is about people's situations that produces the behaviour.

Five causes, each with a mechanism:

• Norms. Behaviour is patterned by what is usual in a person's setting. Where most people around you smoke, or drink heavily at every social occasion, the behaviour requires no decision and abstaining does.
• Stress and coping. Chronic stress from insecure work, money or housing makes short-term relief valuable. Smoking, drinking and eating for comfort are effective coping strategies in the short term, which is exactly why they persist against long-term costs.
• Availability and marketing. Behaviour follows environment. Where fast food outlets are dense and fresh food is expensive or distant, diet follows — and advertising is not distributed evenly across suburbs either.
• Control and hopelessness. Health behaviour is an investment in a future. Where people have little control over their circumstances and less confidence in that future, the trade-off that makes prevention rational weakens.
• Identity and belonging. Behaviours carry meaning. Drinking, risk-taking or a particular diet can be part of belonging to a group, and asking someone to stop is asking more than it appears.

None of this says people have no responsibility. It says behaviour is patterned, and patterns have causes at the level of the group. Once you can see that, the reason health campaigns aimed purely at information disappoint becomes obvious: they treat a shortage of knowledge as the problem when the actual constraint is stress, price, environment or belonging — and the people best placed to act on new information are the ones already advantaged, so a pure information campaign can widen the very gap it was meant to close.

Australian health reports consistently identify particular population groups whose health status is worse than the national average. The groups the syllabus and the reports return to are:

• Aboriginal and Torres Strait Islander peoples, whose health inequities are the product of colonisation, dispossession, and continuing social and economic disadvantage — historical and structural causes rather than cultural ones, which is a distinction worth being precise about in an exam.
• People in rural and remote areas, facing distance from services, fewer health professionals per head, and higher injury risk from work and travel.
• People of low socioeconomic status, across every one of the interactions in Card 05.
• People with disability, facing access barriers of the kinds set out in Lesson 4 and higher rates of several conditions.
• Some culturally and linguistically diverse communities, where language, unfamiliarity with the system and experience of discrimination reduce effective access.

Two cautions, because both are examinable and both are easy to get wrong. These groups overlap, and where they overlap the disadvantages compound rather than adding — the clustering point from Card 05. And none of these groups is uniform: describing any of them as though everyone within it has the same health is exactly the averaging error Lesson 3 warned about, one level down.

Recall the test from Lesson 4: a difference is an inequity when it is avoidable, unnecessary and unfair. Each of these gaps meets that test, and being able to say why it meets it — because the causes are social arrangements that could be otherwise, not fixed facts of biology — is what separates an answer about inequity from an answer about difference.

What can be done. The determinants themselves tell you where the leverage is: act upstream where you can, because that is where the largest population effects sit; direct resources by need rather than uniformly, per Lesson 4; design with participation, since communities know their own barriers; and change environments rather than only informing individuals — the price and availability of food, the safety of streets, the availability of services in a place at a time people can reach.

This card is one idea, and it is the most sophisticated thing in Module 1. It is worth the space because it appears in Year 12 as well, and because it converts everything above into a prediction you can actually use.

An intervention that supplies information — a campaign, a label, a warning — requires the recipient to have the resources to act on it: money, time, transport, security, and a reason to invest in a future. Those resources are exactly what the determinants distribute unevenly. So the people who can act on the information are disproportionately the people already advantaged, and the intervention improves their health first and fastest.

The result is the counter-intuitive part. The intervention works — the average improves, so it will be evaluated as a success — and the gap widens, because the improvement was not evenly distributed. This is why Lesson 3's warning about averages and Lesson 4's insistence on equity are the same argument, and why evaluating a health program means asking who improved and not only whether the mean moved.

The corrective is not to abandon information. It is to pair it with changes to the conditions that let people act — price, availability, environment, services delivered where people are — and to target by need. That is the whole of “what can we do about them”, in a sentence.

For each starting point, build a chain of at least four links running from a determinant down to a health outcome. Label the group each link belongs to, and label every arrow with a mechanism. Then mark where the chain could feed back on itself.

Here is a proposal: a national advertising campaign telling Australians to eat more vegetables and walk 30 minutes a day, run on television and social media for six months.

• Predict which groups will improve most, and explain why using the determinants.
• Explain how the campaign could be evaluated as a success while the gap between groups widens. Name the measure that would show the success and the measure that would show the widening.
• Redesign it. Keep the goal, change the method, and use at least two upstream determinants and at least one social justice principle from Lesson 4.
• State one way you would know whether your redesign had actually narrowed the gap, rather than assuming it.