Objectives: There is a substantial knowledge gap about the distribution of mental health in community populations. The European Social Survey is particularly useful as it contains information on over 40,000 individuals, including 2,286 Irish adults. The objective of this study is to conduct a large scale statistical analysis to examine the distribution and determinants of mental wellbeing in a large representative sample of the Irish population.

Method: Analysis of the European Social Survey using robust multiple linear and non-linear regression techniques. The data-set contains WHO-Five scores and subjective wellbeing for a sample of 2,286 Irish people interviewed in their homes in 2005.

Results: Ireland has the second highest average WHO-Five score among the 22 countries in the European Social Survey. Multiple linear regression analysis across the distribution of WHO-Five reveals a wellbeing gradient largely related to education and social capital variables. A probit model examining the determinants of vulnerability to psychiatric morbidity reveals that a similar set of factors predict scores below the threshold point on the WHO-Five scale.

Conclusions: The results are consistent with marked differences in mental wellbeing across education levels and variables relating to social capital factors. Such indicators provide a useful index for policy-makers and researchers. However, much further work is needed to identify causal mechanisms generating observed differences in mental health across different socioeconomic groups.