Equity

Equity asks whether health, healthcare and the resources that shape them are distributed fairly. This page explains what makes equity different from equality, how different principles of fairness can lead to different conclusions, and how equity can be incorporated into health-economic analysis and decision-making.

Equity is about fairness, not identical treatment

Equity evaluates differences in health, access, financing or resource allocation by asking whether those differences are fair. Equality describes whether people receive the same resources or experience the same outcomes, but equity recognises that people may have different needs, risks, barriers and capacities to benefit.

Providing everyone with the same service is therefore not necessarily equitable. A fair response may require additional resources, adapted services or greater financial protection for people facing greater need or disadvantage.

• Equality gives people the same resources, opportunities or treatment.
• Equity distributes resources, opportunities or treatment according to a relevant principle of fairness.
• Health inequality is an observed difference in health between people or groups.
• Health inequity is a health difference judged to be unfair and avoidable or remediable.
• An equitable policy may treat people differently when those differences respond to unequal needs or barriers.

Fairness can be judged in more than one way

Equity is not a single mathematical rule. Different ethical principles identify different features of a distribution as relevant, so a policy may appear equitable under one principle but not under another.

The principle used should be stated explicitly rather than hidden inside an analysis or decision. Decision makers may consider several principles together when no single principle captures every relevant concern.

• Equity based on need gives greater priority to people with greater health needs.
• Equity based on equal access seeks comparable opportunities to obtain appropriate care.
• Equity based on equal health outcomes seeks to reduce differences in health between groups.
• Equity based on capacity to benefit gives priority where resources can produce meaningful improvement.
• Equity based on severity gives additional importance to people with the most serious conditions or greatest lifetime health losses.
• Equity based on financial protection seeks to prevent healthcare payments from causing hardship.
• Equity based on priority to disadvantaged groups gives additional consideration to people experiencing social, economic or geographic disadvantage.

These principles can conflict. Prioritising the greatest health gain may not reduce health inequalities, while prioritising the most disadvantaged group may produce fewer total health gains from a fixed budget.

Horizontal and vertical equity answer different questions

Horizontal equity asks whether people in relevantly similar circumstances are treated similarly. In healthcare, this may mean that people with equal need should have comparable access to appropriate services, regardless of characteristics that are not considered relevant to care.

Vertical equity asks whether people in meaningfully different circumstances are treated differently in an appropriate way. For example, people with greater health needs may require more intensive services, while households with fewer financial resources may require greater protection from healthcare costs.

• Horizontal equity examines equal treatment for equal need.
• Vertical equity examines appropriately unequal treatment for unequal need.
• The distinction depends on deciding which differences between people are relevant.
• An equity assessment should explain why a characteristic justifies similar or different treatment.

Equity may concern health, healthcare or healthcare financing

Equity can be assessed at several connected levels. A fair distribution of healthcare does not automatically produce equal health because health is also shaped by income, education, housing, environment, employment and other social conditions.

Analysts should therefore state the outcome and population to which an equity claim applies. A policy may improve equity in access while leaving inequalities in health outcomes unchanged, or it may improve average health while worsening financial protection.

• Equity in health concerns the fairness of differences in health status or health outcomes.
• Equity in healthcare access concerns whether people can obtain appropriate services when they need them.
• Equity in healthcare use concerns whether service utilisation reflects relevant need rather than avoidable barriers.
• Equity in healthcare quality concerns whether people receive comparable standards of appropriate care.
• Equity in financing concerns how healthcare payments and financial risks are distributed.
• Equity in resource allocation concerns how budgets, staff, facilities and technologies are distributed across populations.

Efficiency and equity are distinct decision objectives

Efficiency concerns how well resources are converted into valued outcomes. Equity concerns whether the distribution of those resources, opportunities, burdens and outcomes is fair.

The objectives can reinforce one another, but they can also create a trade-off. An intervention may generate the largest total health gain while directing most benefits toward an already advantaged population, whereas another intervention may generate a smaller total gain but reduce an important health inequality.

• An efficient allocation maximises valued outcomes from available resources under the chosen objective.
• An equitable allocation reflects an explicitly justified principle of fairness.
• Efficiency evidence does not determine whether the resulting distribution is fair.
• Equity concerns do not remove the opportunity cost of using resources.
• A transparent decision should report both total effects and their distribution when distribution matters.

Equity should not be treated as an unexplained adjustment made after the economic analysis. It should be incorporated through clearly stated objectives, relevant population groups, appropriate evidence and transparent value judgements.

How equity enters economic evaluation

Conventional economic evaluation often summarises costs and health outcomes across the population. Aggregated results can conceal who gains, who loses, who pays and who is displaced when resources are committed.

An equity-informed evaluation disaggregates relevant effects and examines their distribution alongside the total result. The analytical method should match the decision question and should not imply that a technical calculation can settle every ethical judgement.

1. Define the population and alternatives. Specify whose health, costs, access or financial protection could change under each option.
2. Identify relevant equity characteristics. Select characteristics such as socioeconomic position, geography, ethnicity, sex, disability or disease severity only when they are justified by the decision context.
3. Estimate subgroup effects. Examine how costs, outcomes, access and other consequences differ between relevant groups.
4. Account for opportunity costs. Consider which people may lose health or resources when funding is redirected.
5. Apply an explicit equity principle. State whether the analysis prioritises need, severity, disadvantage, equal access, financial protection or another defensible concern.
6. Compare totals and distributions. Report overall outcomes together with the pattern of gains, losses and burdens across groups.
7. Test uncertain assumptions. Examine whether the equity conclusion changes when subgroup evidence, value judgements or model assumptions change.
8. Present unresolved trade-offs. Distinguish evidence from ethical judgement and show where decision-maker deliberation remains necessary.

Distributional analysis makes hidden effects visible

Distributional cost-effectiveness analysis extends conventional cost-effectiveness analysis by estimating how health benefits and opportunity costs are distributed across relevant population groups. It can show whether an intervention changes total population health, health inequality or both.

Equity weighting is another possible approach in which outcomes received by different people or groups are assigned different social values. Any weighting system depends on normative choices and should therefore be reported transparently, tested in sensitivity analysis and presented alongside unweighted results.

• Subgroup analysis describes how costs and outcomes vary between groups.
• Distributional cost-effectiveness analysis estimates both total health effects and changes in the distribution of health.
• Equity weighting assigns different social values to outcomes according to an explicit fairness principle.
• Multi-criteria decision analysis may place equity alongside efficiency and other decision criteria.
• Extended cost-effectiveness analysis may examine financial risk protection and distributional consequences in addition to health outcomes.

No method removes the need for judgement. The purpose of formal analysis is to make the consequences and value choices more visible, consistent and open to scrutiny.

A simple example of an equity–efficiency choice

Suppose a health system must choose between two programmes using the same limited budget. Programme A produces a larger total health gain, while Programme B produces a smaller total health gain but directs more benefit toward a population experiencing substantially worse health and poorer access to care.

Efficiency evidence may favour Programme A if the objective is to maximise total health. An equity principle based on severity, disadvantage or reducing health inequality may give additional weight to Programme B.

The decision cannot be resolved by describing Programme B as equitable without further explanation. The analysis should state which population is considered disadvantaged, why that difference is ethically relevant, how much total health would be forgone, who bears the opportunity cost and how uncertainty affects the comparison.

Equity claims require careful evidence

Observed differences between groups do not automatically establish inequity. Analysts must distinguish measurable inequality from the judgement that a difference is unfair, while recognising that the evidence needed to explain a difference may be incomplete.

Subgroup estimates can also be uncertain because studies may not include enough participants, measure relevant characteristics consistently or represent populations facing the greatest barriers. An apparently precise equity conclusion may therefore rest on weak or missing distributional evidence.

• Equity analysis should pre-specify relevant groups where possible rather than search for convenient differences after observing the data.
• Equity analysis should report absolute and relative differences because the two measures can lead to different interpretations.
• Equity analysis should consider intersecting characteristics rather than assuming that each characteristic operates independently.
• Equity analysis should distinguish differences caused by need from differences caused by avoidable barriers.
• Equity analysis should report missing data and uncertainty for each relevant group.
• Equity analysis should avoid treating membership of a population group as a complete explanation of individual need or experience.

Common mistakes when interpreting equity

Equity is often weakened when it is used as a general expression of concern without identifying the distribution, population or fairness principle involved. A useful equity claim must say what is distributed, between whom, according to which principle and with what evidence.

Several recurring mistakes can make an assessment appear more conclusive than it is.

• Equity is not the same as giving everyone an identical quantity of care.
• A difference between groups is not automatically an inequity until its fairness and avoidability have been considered.
• Improving average population health does not necessarily reduce health inequality.
• Improving access does not guarantee equal use, equal quality or equal outcomes.
• A subgroup analysis does not become an equity analysis unless the distributional differences are interpreted using an explicit fairness principle.
• Equity weights should not be applied without explaining their ethical basis and testing their consequences.
• Equity should not be presented as cost-free because prioritising one group may create opportunity costs elsewhere.
• A single summary measure should not conceal important gains, losses or burdens experienced by particular populations.

What an equity-informed result should communicate

A clear equity assessment shows both what is known and what remains a matter of judgement. It allows readers to understand who is affected, how the distribution changes and which fairness principle informs the interpretation.

The final presentation should preserve the distinction between empirical evidence and normative choice. Decision makers can then consider efficiency, equity, affordability and other objectives without implying that one measure provides the complete answer.

An equity-informed result should communicate:

• which outcomes, resources or burdens were assessed;
• which population groups were compared and why they were relevant;
• how benefits, harms, costs and opportunity costs were distributed;
• which principle of fairness was applied;
• whether total outcomes and distributional outcomes moved in the same or opposite directions;
• how uncertainty affected the equity conclusion; and
• which value judgements still require transparent deliberation.