Ireland’s measure of basic deprivation and consistent poverty fit for purpose of measuring poverty

Ireland’s existing measures of basic deprivation and consistent poverty, which rely on 11-items from the CSO’s Survey of Income and Living Conditions (SILC) dataset, are appropriate for the measurement of poverty in Ireland. The scale has been used since 2006 for official poverty measures and to track progress in meeting poverty reduction targets. The benefit of a measure of deprivation is that it is a direct and absolute indicator of exclusion arising from lack of resources.

A new ESRI study tested and compared the current 11-item measure using the most recent SILC data from 2019. The current items include the inability to afford new clothing, adequate heating, and replace worn out furniture.  The authors find that a new 15-item measure would be a slight improvement on the current 11-item measure, but that this improvement is minor. Overall, they argue that the current measure captures deprivation well and that there is insufficient evidence to replace or update the scale.  The basic deprivation rate based on the 11-item measure in 2019 was 17.9 per cent and 17.0 per cent on the 15-item measure. The corresponding consistent poverty rates were 5.5 per cent and 5.6 per cent respectively.

Regarding internal consistency - how well all the deprivation items reflect the same underlying concept - the authors used factor analysis to consider 46 potential items of deprivation recorded in the SILC dataset. From this analysis, they found that a new 15-item measure of deprivation would fit the data well, but that the current 11-item measure also performed well in terms of capturing deprivation and consistent poverty.

Regarding validity - how well the measure is associated with other poverty outcomes - both the new 15-item measure, and the current 11-item measure correlate strongly with three measures of financial difficulty: finding it hard to make ends meet, finding that housing costs are a burden, and difficulty facing unexpected expenses. The authors also found a strong correlation between each deprivation measure and being at risk of poverty.

Finally, the report shows that both measures are especially prominent among vulnerable social risk and social class groups. Lone parents (and their children), and adults with a disability (and their children), were especially likely to experience deprivation using either measure. In contrast adults over 65 and adults aged 30-65 were the least likely to report deprivation on either scale. Regarding social class groups, lower social class groups and those who never worked were the most likely to experience deprivation on both scales, while large employers, managers, and professionals were the least likely to report deprivation on either scale. Jobless households were especially likely to experience high level of deprivation in 2019, and this was again recorded by either deprivation scale.

The authors find that the existing 11-item deprivation scale is accurate and fit for the purpose of measuring deprivation and consistent poverty. They further recommend that the measures be reviewed on a regular basis as SILC data becomes available and as standards of living change.

Bertrand Maître, an author of the report said, “Although the 11-item basic deprivation measure could be improved by adding four additional items, we argue that the existing measure performs well and is fit for purpose. To continue measuring trends in deprivation and consistent poverty, policy makers and researchers should keep using the 11-item measure.”

Minister Joe O’Brien, Minister of State with responsibility for social inclusion in the Department of Social Protection said, “The Department and I welcome the publication of the Technical Paper on the Measure of Basic Deprivation and Consistent Poverty in Ireland. It is the first publication under the DSP/ESRI Poverty and Social Inclusion Research Programme 2020-2023.  As living standards can change over time, it is important to ensure that the indicators we use to measure and track poverty and deprivation in Ireland accurately reflect the circumstances of those who are most vulnerable and I was anxious to ensure the measures used are still appropriate. It is reassuring to see that the deprivation indicator currently in use continues to be an accurate measure.”