Skip to main content

Advertisement

Log in

Defining thirds of schooling years in population studies

  • Original Paper
  • Published:
European Journal of Epidemiology Aims and scope Submit manuscript

Abstract

When the schooling years are compared between individuals having different birth years, the steep rise in schooling years in the 20th century must be taken into account. The problem has particular importance in large international population studies, such as the WHO MONICA Project and its successor, the MORGAM Project. We present an algorithm that divides the individuals into three groups on the basis of the schooling years while preserving smooth behavior of the cut-points between consecutive birth years. The usage of method is demonstrated with data from Finland, Italy, Lithuania, and Scotland, which have different patterns of the estimated tertiles of schooling years.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2

Similar content being viewed by others

Abbreviations

MONICA:

Multinational MONItoring of trends and determinants in CArdiovascular disease

MORGAM:

MOnica Risk Genetics Archiving and Monograph

WHO:

World Health Organization

References

  1. Kunst AE, Mackenbach JP. The size of mortality differences associated with educational level in nine industrialized countries. Am J Public Health 1994;84(6):932–7.

    Article  PubMed  CAS  Google Scholar 

  2. Mackenbach JP, Kunst AE. Measuring the magnitude of socio-economic inequalities in health: an overview of available measures illustrated with two examples from Europe. Soc Sci Med 1997;44(6):757–71.

    Article  PubMed  CAS  Google Scholar 

  3. Molarius A, Kuulasmaa K, Moltchanov V, Ferrario M. for the WHO MONICA Project. Quality assessment of data on marital status and educational achievement in the WHO MONICA Project, Available from http://www.ktl.fi/publications/monica/educ/educqa.htm, URN:NBN:fi-fe19991078. 1998.

  4. Dobson A, Kuulasmaa K, Moltchanov V, Evans A, Fortmann SP, Jamrozik K, Sans S, Tuomilehto J. for the WHO MONICA Project. Changes in cigarette smoking among adults in 35 populations in the mid 1980s. Tob Control 1998;7:14–21.

    Google Scholar 

  5. Tunstall-Pedoe H (ed). MONICA monograph and multimedia sourcebook. World Health Organization, Geneva, 2003.

    Google Scholar 

  6. Evans A, Salomaa V, Kulathinal S, Asplund K, Cambien F, Ferrario M, Perola M, Peltonen L, Shields D, Tunstall-Pedoe H, Kuulasmaa K, for the MORGAM Project. Cohort profile: MORGAM (an international pooling of cardiovascular cohorts). Int J Epidemiol 2005;34(1):21–7.

    Google Scholar 

  7. R Development Core Team, R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria, 2006, http://www.R-project.org, ISBN 3-900051-07-0.

  8. Royston P, Altman DG, Sauerbrei W. Dichotomizing continuous predictors in multiple regression: a bad idea. Stat Med 2006;25:127–41.

    Article  PubMed  Google Scholar 

Download references

Acknowledgements

The authors thank Prof. Jaakko Tuomilehto, National Public Health Institute, Prof. Abdonas Tamosiunas, Institute of Cardiology, Prof. Hugh Tunstall-Pedoe, University of Dundee, Prof. Giancarlo Cesana, Università degli studi di Milano-Bicocca and Prof. Marco Ferrario, Università degli studi dell’Insubria for making their MONICA data available and commenting the manuscript. This work was supported by the GenomEUtwin Project grant from the European Commission under the programme ‘Quality of Life and Management of the Living Resources’ of 5th Framework Programme (No. QLG2-CT-2002-01254) and by the Academy of Finland via its grant number 53646.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Juha Karvanen.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Karvanen, J., Veronesi, G. & Kuulasmaa, K. Defining thirds of schooling years in population studies. Eur J Epidemiol 22, 487–492 (2007). https://doi.org/10.1007/s10654-007-9144-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10654-007-9144-z

Keywords

Navigation