Het uitsluiten van geïnstitutionaliseerde ouderen in surveys: gevolgen voor de Open Coördinatiemethode Pensioenen

Abstract

In comparative European surveys it is common practice to exclude elderly people living in collective households from the sampling frame. This article examines the implications of this practice for the validity and international comparability of indicators in the Open Method of Coordination on Pensions (Pensions OMC). Analyses using data from the Belgian Datawarehouse Labour Market and Social Protection show that the resulting bias is negligible for average equivalent pension income, but that poverty among pensioners is underestimated by 9%. In subgroups such as the oldest pensioners the underestimation is even larger. Due to the major international differences in the percentage of elderly in collective households, this bias also jeopardizes the international comparability of poverty indicators in the Pensions OMC. This renders the identification of best practices in the Pensions OMC unreliable. Furthermore, it may nourish an unconstructive politics of indicators which in the longer term undermines the credibility and effectiveness of the Pensions OMC.