Joint Programming Initiative

More Years, Better Lives

The Potential and Challenges of Demographic Change

Betula - aging, memory and dementia
Betula – åldrande, demens och minne

Health and Performance
Relevance for this Topic
Country Sweden
More Topics


Contact information

Lars-Göran Nilsson, principal investigator
Department of Psychology / Stockholm University
106 91 Stockholm
Phone: +46-8-163940
Fax: +46-8-159342
Email: lgn(at)

Timeliness, transparency

Depends due to number of ongoing studies. Usually one year or more.

Type of data


Type of Study

Longitude survey: long-term study of random or different samples

Cohort study

Data gathering method

Face-to-face interview (CAPI, PAPI)

medical, physical and cognitive tests. Also genetic data and biological samples are connected to the Betula database.

Access to data

Someone who wants to use Betula data will have to fill in an application according to what is shown below. The forms for such applications are called DTA (Data Transfer Agreement) and MTA (Material Transfer Agreement). These forms will be available here soon. It is shown in the forms which information that has to be provided and to whom the forms should be sent.

Conditions of access

The applicant who aim at using cognitive and health data, biological samples and brain imaging materials from Betula must submit: 1. Research proposal, 2. CV, and 3. Application or Approval from Ethics Committee. When access to Betula data or materials has been granted, the responsible researcher for a given data set is required to submit a progress report by the dates given in the signed agreement

Decisions are taken two times per semester – application should be sent the month before the meeting, if not the processing will be prolonged. Around two months in general.

Anonymised microdata. But also Betula offers the possibility for external researchers to get access to data on cognition and health, blood and DNA samples, and neuroimaging data. For this to materialize some general considerations and specific rules need to be stated.

Usually SAS, SPSS, Excel and texts (and others on request – see above)

Code book in English is available upon request. The SPSS database is in the process of being transferred to MYSQL. Data is available both in Swedish and in English.


The Betula Project is a longitudinal study of aging, memory and dementia. It has been going on in Umeå since 1988. In September 2013, a sixth data collection will begin. It is expected to be completed in March 2015. The participants of the project have been tested, interviewed and examined medically at five occasions (1988-1990, 1993-1995, 1998-2000, 2003-2005 and 2008-2010). The main objectives of the project is to study how memory functions and health change during adult life and old age, to identify risk factors for dementia and to identify early preclinical signs of dementia. Then the study began with including 1000 randomly selected individs from the Umeå municipality in the age groups 20, 35, 40, 45, 50, 55, 60, 65, 70, 75 and 80 years. It was 100 in each age cohort, and the gender distribution was similar to the population with about as many men as women in the younger age groups, and about twice as many women as men in the age groups 70 and over. Five years later, two more sample were included. The group has been monitored every five years: 1993, 1998, 2003 and 2008. A sixth wave of data collection is starting in September 2013. For each sample, each participant completed a thorough physical examination with blood tests of a nurse and a careful examination of a memory tester. There are data collected from approximately 4,700 participants. On each occasion, data for about 2000 variables were collected for each participant, which includes data on demographics, health, illness, medication, social and cognitive factors.


Mainly region of Västerbotten (around Umeå)

sample from City of Umeå

Individuals 20 to 80 years old; At present, those participants still alive in Betula are 25-100 years of age.

City of Umeå

The Betula project is a very multi-disciplinary research project with researchers from many different fields: psychology, neurophysiology, brain imaging, genetics, gerontology, computer simulations.

• Kauppi, K., Nilsson, L.-G., Adolfsson, R., et al. (in press). “Decreased medial temporal lobe activation in BDNF 66Met allele carriers during memory encoding.” Neuropsychologia. DOI: 10.1016/j.neuropsychologia.2012.11.028. • Nixon Andreasson, A., Szulkin, R., Undén, A.-L., et al. (in press). “Inflammation and positive affect related to subjective health: Women from the general population.” Journal of Health Psychology 18(3) (2013): 311-320 DOI: 10.1177/1359105311435428 • Piper, B.J., Yasen, A. L., Taylor, A. E., et al. (in press). “Non-replication of an association of Apolipoprotein E2 with sinistrality.” Laterality, iFirst, 1-11. DOI: 10.1080/135765X.2012.660164 • Rönnlund, M., Carlstedt, B., Blomstedt, Y., et al. “Secular trends in cognitive performance: Swedish conscript data 1970-1993.” Intelligence 41 (2013): 19-24. • Rönnlund, M., Sundström, A., Eriksson, D., & Nilsson, L.-G. “Effects of perceived long-term stress on subjective and objective aspect of memory and cognitive functioning in a middle-aged population-based sample.” Journal of Genetic Psychology 173 (2013): 1-17. Find publications from the Betula-project in the Annual Report of the Department of Psychology, Stockholm university.


The Betula project has not dealt with these standards and taxonomies. This is primarily a study on cognitive psychology, neuropsychology, brain imaging, genetics, neurophysiology, with many demographic variables like gender, age, education, illness of participants, illness of relatives, medication, life style, marital status etc.

Betula is used in many scientific settings (SWEDOLD, Linneaus database and many orhers) A running ID number of all participants exists. Participants are additionally identified by gender and age (in combination with the running ID number.)

Data quality

After each wave of data collection there is a careful quality check of the data collected. In addition, we do another quality check of the data now, when we are in the process of transferring the SPSS format to a MySQL format.

The basic methodology design has been kept the same since the start of Betula in 1988. Some cognitive tests used originally have been deleted and others have been added primarily because of theoretical and methodological development in cognitive psychology, neuropsychology, neuroscience, brain imaging and other fields. Additional health tests have been added during the course of the project. For example, a very large sub-database has been added on oral health, bilingualism, hormones and women issues during menopause, cytokines, extensively on dementia, herpes virus, genetics (from single gene analyses to GWAS), brain imaging (structural and functional MRI, and PET data on some participants), for some social variables (primarily economic variables) we can connect to a database over the whole population of Sweden, in connection with another database we can relate Betula data to an extensive database on health and nutrition, in connection with still another database we can connect Betula participants to cause of death and diseases. We have also blood saved from 1988and saliva saved saved from 2005.

Terminology is the same since 1988, except from a few cognitive tests that are classified differently now as compared to 1988 due to the development of theory and methodology in the field.


Strengths The Betula project has received funding for research infrastructures (large databases) from the Swedish Research Council. This means a major effort to make the Betula database available to researchers outside the project. The plan is that researchers granted access to Betula data will work against a closed system with terminals connected to a server to do their analyzes. The Betula Project is designed to make both cross-sectional and longitudinal analyses of the data for proper control of cohort effects, test-retest effects and effects of attrition. All participants are randomly sampled from the population registry of the city of Umeå. The attrition rate other than death is much lower in Betula than in any other ongoing study in the world. There is a very large number of variables used at each data collection (approximately 2000 variables). Weaknesses The data collections are very costly.

  • The information about this dataset was compiled by the author:
  • Kenneth Abrahamsson
  • (see Partners)