• Title: SOEP-BASE
  • Berlin Aging Study II
  • Bertram et al., 2014. Cohort Profile: The Berlin Aging Study II (BASE-II), International Journal of Epidemiology, 43(3), 703-712.
  • Boeckenhoff et al., 2013. The Socio-Economic Module of the Berlin Aging Study II (SOEP-BASE): Description, Structure, and Questionnaire, SOEPpapers on Multidisciplinary Panel Data Research 568.
  • Persistent identifier (e.g. DOI): NA
  • Investigators/authors: Gert G. Wagner; Martin Kroh

  • URL: [BASE-II] (|


Study Info

The Berlin Aging Study II (BASE-II) is an extension and expansion of the Berlin Aging Study (BASE). This new study with more than 2,200 participants of different ages aims to complement the analysis of cognitive development across the lifespan by including socio-economic and biological factors such as living conditions, health, and genetic preconditions. The study is funded by the Federal Ministry of Education and Research.


The sample consists of a cohort of around 1,600 older individuals (aged 60-75 in 2009) and a cohort of 600 younger individuals (aged 20-35 in 2009). In both cohorts males and females are equally represented. The participants were recruited from earlier studies conducted at the Max-Planck-Institute for Human Development. Additional participants were recruited by means of advertisement in newspapers and public transport. For the subproject “Survey Methods and Social Science” the BASE-II participants answer questionnaires on a number of topics, ranging from income and labor market participation to health and personality. The questionnaires were developed in accordance with the SOEP instruments. Participating households receive one household questionnaire and a each householad member receives a personal questionnaire (including members who do not participate in the other parts of the BASE-II study). The survey has been conducted in 2008 (for the “Cogito” sub-sample), in 2009 (for the “Cogito” and “Dopamin” sub-sample), in 2010 (again for the “Cogito” sub-sample) and in 2012 and 2014 (for the whole sample). In 2012, data on 2,100 individuals were collected, of whome 1,500 are participants in the BASE-II study. The latest survey in 2014 collected data on 2232 individuals living in 1536 households.

Main Survey Modes by Wave and Subpopulation

year 2008 2009 2010 2012 2014 Individuals
L1 CAPI CAPI Mail CAWI/ Mail - 232
L2 - CAWI/ Mail not surveyed CAWI/ Mail - 1924
L3 - - - CAWI/ Mail - 182
L4 - - - - CAWI/ Mail 2232

Data access

The BASE-II data are available to external users. Data access is contingent upon approval of the BASE-II steering committee. The application for data access should include an abstract of the intended research project, a data protection statement as well as a completed application form. The necessary forms and further information can be obtained from Dr. Katrin Schaar (> Researchers interested in using the medical, psychological or genetic data are advised to contact the respective research units first before applying for data access.

Data description

The SOEP-BASE data includes cross-sectional datasets for each year and for both the personal and household questionnaire. In addition, the data are available in one longitudinal dataset, which contains data from all years and both instruments. All datasets include a person-identifier (Variable pnrfest) and a household identifier (Variable hnr). Cross-sectional weights are available for the years 2009, 2012 and 2014. Longitudinal weights are available for 2012 and 2014. The longitudinal dataset also includes an identifier that allows linking the SOEP-BASE data to data from other BASE-II subprojects (e.g., medical or cognitive data). The variable names are documented in the annotated questionnaires.

Missing conventions

Code Meaning
-1 missing information
-2 does not apply
-3 invalid information

Other material and Notes

Anke Böckenhoff, Denise Saßenroth, Martin Kroh, Thomas Siedler, Peter Eibich and Gert G. Wagner (2013): The Socio-Economic Module of the Berlin Aging Study II (SOEP-BASE): Description, Structure, and Questionnaire. SOEPpapers 568 Berlin

TNS Infratest Sozialforschung (2015): SOEP-RS BASE II 2008-2014 – Erhebungsinstrumente Berliner Altersstudie II. SOEP Survey Papers 269

Study info

Name: soep-base

Label: BASE II

Datasets: 10

Variables: 5267

Instruments: 0

Questions: 0


Name Label Conceptual Period Analysis unit
h2012 h2012 org/net 2012 h
soep-base-long soep-base-long gen long
l2009 l2009 org/net 2009 p
p2008 p2008 org/net 2008 p
h2008 h2008 org/net 2008 h
p2009 p2009 org/net 2009 p
h2009 h2009 org/net 2009 h
p2010 p2010 org/net 2010 p
h2010 h2010 org/net 2010 h
p2012 p2012 org/net 2012 p


Name Label Period Analysis Unit

Contact / feedback

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