The Danish Conscription Database - DCD

The steering group of the Danish Conscription Database welcomes collaboration and the interest of national and international colleagues.
If you have any questions regarding the database, please contact Sissel Skogstad or Drude Molbo  

In order to access the database please submit the research protocol to project leader Erik Lykke Mortensen.

Once the project has been approved a collaboration agreement must be completed. The database will subsequently be made available upon final approval by the steering committee and Danish Data Protection Agency.

The establishment of the Danish Conscription Database (DCD)

The DCD was established in 2008-2013 by digitizing selected information from the Danish conscript board register cards. The conscript board examinations have been conducted according to national guidelines and the information collected has been recorded in a standardized format in register cards from the mid 1950’ies through 1986 and from then on the information collected has been stored electronically. In 1957 an intelligence test was implemented in the conscript board examination, and from 1957 through 1978 the information was uniformly measured. In 1979 the educational registration was altered, while the registration of the other data remained the same.

The funding was insufficient to digitize all of the available register cards. Moreover, the organization of the cards made it difficult to delimitate to either year of conscript board examination or year of birth. It was decided to digitize complete archive units, so that the majority of men from the 21 birth cohorts from 1939-1959 was included, because these men would predominantly have been examined in the period from 1957 through 1978 in which the data was uniformly measured. In the database the two outer birth cohorts, 1939 and 1959, are not as complete as the intermediate cohorts, as some of the men’s cards were located in archival units that were not digitized.

Who is in the cohort?

All Danish men are requested at age 18 to appear before the conscript board and only a small percentage is exempted due to medical conditions. Boys volunteering for military service before their 18th birthday are also exempted from appearing. In the DCD the exempts are registered with personal identification details and no examination data from the conscript board.

To assess the completeness of the database the birth cohorts from the database was compared with the number of men from the corresponding birth cohorts in the Statistical Yearbook. For the years 1940 to 1958, the coverage rate is 81.2% to 95.2%, while the coverage rate is lower for the years 1939 and 1959 due to the regional disparities in the archiving of register cards (see figure). Furthermore, register cards from the reunited southern part of Jutland (district 7/see map) for the birth cohort 1952-1954 were lost due to a flooding.

Variables in the database

The selected variables to be digitized were: identifying information (either name, date of birth and place of birth/ address when at conscript or personal identification number (CPR-number)), conscript board district (see map), time of conscript board examination (the year and half-year), height (measured without shoes), weight (measured with underwear), educational level, and intelligence test score (9 categories).

The intelligence test comprises four subtests which assess the logical, verbal, numerical and spatial abilities, and has been administered uniformly in the period from 1957 and up to today. For a more detailed description of each variable see list of variables.

Identification of CPR-numbers

A total of 741.636 unique conscript register cards were digitized. About 70% of the men were registered with a CPR-number and the vast majority of these men could be linked directly to the CPR-register. The remaining 30% attended the conscript board before the introduction of CPR-numbers in 1968, and hence were only registered by name and date of birth. A custom made matching program was used to identify the CPR-number for these 30% by matching name and date of birth from the register cards with name and date of birth from the CPR-register. In total 728.160 (98,2 %) of the entered men were identified in the CPR-register, and this population constitutes the database

Erik Lykke Mortensen
(Chairman and Principal investigator)
Professor, MSc in Psychology
Section of Environmental Health
Institute of Public Health
University of Copenhagen
Copenhagen
Denmark
Direct: +45 3532 7839
Email: elme@sund.ku.dk

Merete Osler Professor
DMSc, PhD
Center for Clinical Research and Prevention Bispebjerg and Frederiksberg Hospitals
Frederiksberg
Denmark
Direct: +45 3816 3100
Email: merete.osler@regionh.dk
Mobile: +45 4010 4312

Kaare Christensen
Professor, Dr.Med.Sci PhD
Danish Ageing Research Center
Institute of Public Health
University of Southern Denmark
Odense
Denmark Direct: +45 6550 3049
Email: kchristensen@health.dk

Thorkild IA Sørensen
Professor, dr.med.sci.
Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen and
Section of Epidemiology, Institute of Public Health, University of Copenhagen
Copenhagen
Denmark
Direct:+45 9356 5934
Email: tias@sund.ku.dk

Gunhild Tidemann Christensen
PhD, MSc
Center for Clinical Research and Prevention Bispebjerg and Frederiksberg Hospitals
Frederiksberg
Denmark
Email: gunhild.tidemann.christensen@regionh.dk

Drude Molbo
PhD, MSc
Section of Social Medicine
Institute of Public Health
University of Copenhagen
Copenhagen
Denmark
Email: drmo@sund.ku.dk

Sissel Skogstad
MSc Section of Social Medicine
Institute of Public Health
University of Copenhagen
Copenhagen
Denmark
Email: sisk@sund.ku.dk

If you have any questions regarding the database, please contact

Sissel Skogstad  
E-mail: sisk@sund.ku.dk

or

Drude Molbo
E-mail: drmo@sund.ku.dk