Biomarker Consent Analyses

In recent years, there has been an upsurge in the use of biological specimens as objective health measurements in socio-economic surveys. High participation rates in the collection of biomarkers are desirable to enhance the statistical power by increasing the number of observations available for statistical analyses. Consent rates may depend on many factors. This report looks at the consent rates for the collection of dried blood spots (DBS) samples in the context of the sixth Wave of the Survey of Health, Ageing and Retirement in Europe (SHARE) and focusses on two of them: different legal or ethical requirements in the participating countries and the expectations of SHARE interviewers regarding the success of the DBS collection. The analyses of these factors in correlation with actual consent rates suggest that the interviewers’ expectations have been more important for the success of the blood collection in terms of higher consent rates than specific deviations regarding the collection process based on legal and ethical requirements. This is an interesting result for survey practitioners who are concerned with the integration of the collection of biomarkers in socio-economic surveys: whereas legal or ethical requirements cannot be changed easily, the expectations of the interviewers can be influenced by good interviewer training.