Comparing health of migrant and native populations : Testing intercultural and longitudinal measurement equivalence of the SF-12 using Structural Equation Modelling

Response-sets belong to reoccurring problems in migration research. Cultural factors, time-varying effects and survey design lead to response biases. It could be shown that depending on the region of origin, migrants tend to extreme or centred responding behaviour. Macroscale changes in attitudes towards disclosure of personal information influence acquiescent biases. Therefore, the question arises whether the presence of measurement equivalence can be assumed, especially within instruments regarding subjective feelings, when differences between migrant and native populations are the variable of interest. The aim of the study is to test for intercultural and longitudinal equivalence of the Short Form 12 - items scale (SF -12), trying to answer the question whether this instrument is useful to compare health of migrants and native Germans over time. The study contributes to the ongoing discussion on measurement equivalence of the SF -12 by including variables concerning integration and assimilation, employment, family status and varying types of migration and years since migration to the analysis. Using longitudinal data from the German Socioeconomic Panel (SOEP) and a Structural Equation Modelling approach, Different Item Functioning can be detected for a series of covariates. The study concludes in recommending a reduced version of the SF-12 to improve the avoidance of measurement artefacts when comparing the health of migrants and native Germans