Talk 1: Rob Young, MRC Functional Genomics Unit, University of Oxford: What is the shape of the dose-response relationship between markers of socioeconomic status and health status indicators?
The association between socioeconomic status (SES) and health status has been extensively studied as a linear one, but this assumption of linearity is rarely tested. We have developed a novel technique based on spline theory which calls turning points, known as ’knots’, within this linear relationship. Both the number and the position of these knots can be estimated using various standard regression models. The results of this modelling are summarised graphically and by two summary statistics ’ the Population Attributable Risk (PAR) and the Relative Index of Inequality (RII). We have used this approach to observe a significant increase in the strength of the positive association between the Scottish Index of Multiple Deprivation (SIMD) and the rate of hospital admissions due to alcohol misuse after reaching the bottom 10% of SIMD scores. When modelling a categorical variable such as education status we find that accounting for the population distribution can remove significant non-linearity even when analysing individual-level data. This new method improves the accuracy of traditional regression modelling while preserving much of its parsimony and, with the use of standard reporting statistics, its ease of interpretation.
Rob Young has just completed a six-month fellowship at the Scottish Collaboration for Public Health Research and Policy looking at non-linearity in the relationship between SES markers and health status indicators. This fellowship was a break at the end of the 3rd year of his DPhil based in the MRC Functional Genomics Unit, University of Oxford where he worked both computationally and experimentally on noncoding RNAs in the fruit-fly, Drosophila melanogaster.
Talk 2: Frank Popham, School of Geography and Geosciences, University of St Andrews: Comparing health inequalities in Scotland to elsewhere in Europe.
There is growing interest in how the extent of socio-economic inequalities in morbidity and mortality varies across countries. In Europe there have been a number of major comparative studies, the most recent of which covered data from the 1990s. However, Scotland has not been included in this work. So using data from the 1990s and 2000s the aim of the project was to replicate the most recent European work in Scotland. This talk will present the results.
Frank Popham is a research fellow in the School of Geography and Geosciences at the University of St Andrews. He has a social science background and his main research interests are health inequalities and population health.