Applying clinical epidemiological methods to health equity: the equity effectiveness loop

Introduction

The world achieved impressive health gains during the 20th century.¹ However, health worldwide is distributed unevenly, according to socioeconomic status.^2-4 Unfair and avoidable health inequalities have been termed health inequities.⁵ Modern health policy must ensure that poor people are included in the benefits of development.⁶

Objective

We propose the “equity effectiveness loop” framework (fig 1) to highlight equity issues inherent in assessing health needs, effectiveness, and cost effectiveness of interventions, and the development and evaluation of evidence based health policy. This framework provides a method to calculate the “equity effectiveness ratio,” which assesses the impact of various factors on the gap in the effectiveness of interventions across socioeconomic gradients. Although we illustrate the application of this approach when data are available on the economic gradient across individuals, if socialgroup attributes are also known, the approach could be applied for other equity factors as illustrated by the PROGRESS concept: place of residence; race, ethnicity, and culture; occupation; sex; religion; education; socioeconomic status; and social capital, which reflects categories across which disadvantage may exist.⁷ Including equity issues is an improvement on the iterative measurement loop, which focused on averages and thus ignored the distribution of health effects.^{8 9}

Information on the distribution of both “risk” and “response” across the wealth gradient is critical for going beyond mere measurement to designing strategies to reduce the health gap between rich and poor.

Methods

This equity effectiveness loop provides a framework for developing and evaluating population health interventions and policies that explicitly focus on narrowing the gap between rich and poor, using the best …