An economic evaluation should explore the equity implications of implementing the intervention.

Importance to decision making

The equity implications of implementing an intervention within a given constituency are important, because decisions concerning resource allocation in health frequently reflect considerations other than efficiency. Important equity considerations may include issues such as whether equal access is given to those in equal need, whether resources are distributed fairly to those with different levels of need, or recognising that interventions such as smoking cessation programmes may simultaneously increase population health and health inequalities. Limiting an economic evaluation to a determination of cost-effectiveness across a population as a whole ignores differences in the capacity to benefit and/or in access to care, and may prevent the decision-maker from appropriately considering the differential impacts of a decision on different subgroups within the population.

It is worth noting that in adhering to certain principles in the Gates-RC some equity implications will be considered implicitly. For example, exploring heterogeneity may involve a consideration of distributional implications of implementing an intervention. However, adherence to the other principles of the Gates-RC will not generally be sufficient to ensure that the equity implications of a decision problem have been adequately explored. For this reason, exploration of equity is a principle that should be addressed in its own right in BMGF-funded economic evaluations.

Method specification
There are many dimensions to assessing the equity implications of a proposed intervention. Methods employed may be qualitative, such as the seven-step analysis (as used in Miljeteig 2010[1]), or may involve the quantitative assessment of distributive impact and expected trade-offs, using established mechanisms such as the Atkinson index or Gini index. At the most basic level, an exploration of the equity impact may involve a description of particular groups within the constituency that may be disproportionally affected (positively or negatively) by a decision. Adherence to the equity principle is not, however, simply a matter for reporting results. Equity implications should be considered at all stages of an economic evaluation, including the design, analysis and reporting stages. This is important for all types of economic evaluation, including those undertaken along-side clinical trials.

It is not proposed that the Gates-RC be prescriptive about the methods to be used or how equity implications are presented. However, as experience increases, subsequent iterations of the Gates-RC might provide greater guidance for researchers and decision-makers in considering the equity implications of resource allocation decisions in health.