Johan P Mackenbach1, Pekka Martikainen2, Gwenn Menvielle3, Rianne de Gelder1. 1. Department of Public Health, Erasmus MC, Rotterdam, The Netherlands. 2. Department of Sociology, University of Helsinki, Helsinki, Finland. 3. Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France.
Abstract
BACKGROUND: Reducing inequalities in health is a great challenge for public health, but how relative and absolute inequalities in mortality respond to changes in mortality by socioeconomic group is not well understood. METHODS: We derived arithmetically what combinations of changes and starting levels of mortality by socioeconomic group produce narrowing, and what combinations produce widening of relative and absolute inequalities in mortality. We then determined empirically how often these scenarios actually occur with data on inequalities in cause-specific mortality in five European countries spanning four decades (1970-2010). RESULTS: Changes in the rate ratio depend exclusively on the ratio of relative mortality change between socioeconomic groups, whereas changes in the rate difference depend on whether the ratio of relative mortality change between socioeconomic groups is larger or smaller than the rate ratio. This implies that, in case of declining mortality and faster relative mortality decline in higher socioeconomic groups, the rate difference will increase until the rate ratio becomes equal to the ratio of relative mortality decline, but will then start to decline. In the most common scenario in our data set (starting rate ratio above 1.00 and faster relative mortality decline in higher than lower socioeconomic groups), the rate ratio indeed always goes up but the rate difference goes down in about half of all cases, sometimes after a period of growth. CONCLUSIONS: A narrowing of absolute inequalities occurs under a wider range of conditions than a narrowing of relative inequalities in mortality. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
BACKGROUND: Reducing inequalities in health is a great challenge for public health, but how relative and absolute inequalities in mortality respond to changes in mortality by socioeconomic group is not well understood. METHODS: We derived arithmetically what combinations of changes and starting levels of mortality by socioeconomic group produce narrowing, and what combinations produce widening of relative and absolute inequalities in mortality. We then determined empirically how often these scenarios actually occur with data on inequalities in cause-specific mortality in five European countries spanning four decades (1970-2010). RESULTS: Changes in the rate ratio depend exclusively on the ratio of relative mortality change between socioeconomic groups, whereas changes in the rate difference depend on whether the ratio of relative mortality change between socioeconomic groups is larger or smaller than the rate ratio. This implies that, in case of declining mortality and faster relative mortality decline in higher socioeconomic groups, the rate difference will increase until the rate ratio becomes equal to the ratio of relative mortality decline, but will then start to decline. In the most common scenario in our data set (starting rate ratio above 1.00 and faster relative mortality decline in higher than lower socioeconomic groups), the rate ratio indeed always goes up but the rate difference goes down in about half of all cases, sometimes after a period of growth. CONCLUSIONS: A narrowing of absolute inequalities occurs under a wider range of conditions than a narrowing of relative inequalities in mortality. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Keywords:
Epidemiological methods; Health inequalities; MEASUREMENT; MORTALITY
Authors: Jens Hoebel; Alexander Rommel; Sara Lena Schröder; Judith Fuchs; Enno Nowossadeck; Thomas Lampert Journal: Int J Environ Res Public Health Date: 2017-09-26 Impact factor: 3.390
Authors: Jens Hoebel; Jonas D Finger; Benjamin Kuntz; Lars E Kroll; Kristin Manz; Cornelia Lange; Thomas Lampert Journal: BMC Public Health Date: 2017-06-06 Impact factor: 3.295