Study design,exposure variables,and socioeconomic determinants of participation in Diet,Cancer and Health: A population-based prospective cohort study of 57,053 men and women in Denmark

Abstract

Aims: Diet is considered an important aspect of lifestyle related to cancer development. To contribute further knowledge within this field a Danish prospective cohort study ``Diet, Cancer and Health'' has been initiated. The aims of this paper are to give a description of the study design, measurement procedures, and differences between participants and nonparticipants with special reference to socioeconomic characteristics. Methods: A total of 160,725 individuals 50—64 years of age living in Copenhagen or Aarhus were invited to participate. Information concerning diet and other lifestyle factors was obtained from 57,053 participants using questionnaires and interviews. Anthropometric measurements were taken and biological material collected. In addition, detailed (selected) socioeconomic information on all invited persons including 103,671 non-participants was obtained from statistical registers in Statistics Denmark. Results: Differences were seen between participants and non-participants on a number of socioeconomic factors. The highest participation in relation to education was found among participants with higher education, with a significant tendency to be highest in the second highest level of higher education (3—4 years). Married people were more likely to participate than persons living alone or cohabiting. Conclusion: Results from the prospective cohort study ``Diet, Cancer and Health'' support the general assumption that lower socioeconomic groups are underrepresented in epidemiological studies.

Keywords

Cancer diet measurement procedures participation prospective cohort socioeconomic determinants study design

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References

Tannenbaum A. Initiation and growth of tumours; introduction: effects of underfeeding. Am J Cancer 1940;39:335—50.

Armstrong B. , Doll R. Environmental factors and cancer incidence and mortality in different countries, with special reference to dietary practices . Int J Cancer 1975;15:617—31.

World Cancer Research Fund , Food, nutrition and the prevention of cancer: a global perspective. Washington, DC: World Cancer Research Fund in Association with American Institute for Cancer Research; 1997.

Giovannucci E. , Stampfer MJ , Colditz GA , Manson JE , Rosner BA , Longnecker M. , et al. A comparison of prospective and retrospective assessments of diet in the study of breast cancer. Am J Epidemiol 1993;137:502—11.

Riboli E. , Hunt KJ , Slimani N. , Ferrari P. , Norat T. , Fahey M. , et al. European Prospective Investigation into Cancer and Nutrition (Epic): Study populations and data collection. Public Health Nutr 2002;5:1113—24.

Central Population Registry , Orientering Om mulighederne for udtræk fra det centrale personregister [Information on data processing in the central population registry]. Central Population Registry, 1980. p. 1—13.

Overvad K. , Tjonneland A. , Haraldsdottir J. , Ewertz M. , Jensen OM Development of a semiquantitative food frequency questionnaire to assess food, energy and nutrient intake in Denmark. Int J Epidemiol 1991;20:900—5.

Tjonneland A. , Overvad K. , Haraldsdottir J. , Bang S. , Ewertz M. , Jensen OM Validation of a semiquantitative food frequency questionnaire developed in Denmark. Int J Epidemiol 1991;20(4):906—12.

Tjonneland A. , Haraldsdottir J. , Overvad K. , Stripp C. , Ewertz M. , Jensen OM

Influence of individually estimated portion size data on the validity of a semiquantitative food frequency questionnaire. int

J Epidemiol 1992;21:770—7.

10.

Haraldsdottir J. , Tjonneland A. , Overvad K. Validity of individual portion size estimates in a food frequency questionnaire. Int J Epidemiol 1994;23:786—96.

11.

Stripp C. Use of global questions in a semiquantitative food frequency questionnaire to adjust for the possible over-estimation of the intake of fruit and vegetables. Eur J Clin Nutr 1998;52:S46.

12.

Lauritsen J. Foodcalc 1.3. Computer Program. 1998. Available at: http://www.foodcalc.dk.

13.

Lukaski HC , Johnson PE , Bolonchuk WW , Lykken GI Assessment of fat-free mass using bioelectrical impedance measurements of the human body . Am J Clin Nutr 1985;41:810—17.

14.

Tjonneland A. , Overvad K. , Thorling E. , Ewertz M. Adipose tissue fatty acids as biomarkers of dietary exposure in Danish men and women. Am J Clin Nutr 1993;57:629—33.

15.

Ware JE, Jr , Sherbourne CD The MOS 36-Item Short-Form Health Survey (Sf-36). I. Conceptual framework and item selection. Med Care 1992;30:473—83.

16.

Storm HH , Michelsen EV , Clemmensen IH , Pihl J. The Danish Cancer Registry—History, content, quality and use. Dan Med Bull 1997;44:535—9.

17.

Juel K. , Helweg-Larsen K. The Danish Registers of Causes of Death. Dan Med Bull 1999;46:354—7.

18.

Andersen TF , Madsen M. , Jorgensen J. , Mellemkjaer L. , Olsen JH The Danish National Hospital Register: A valuable source of data for modern health sciences. Dan Med Bull 1999;46:263—8.

19.

Thygesen L. The register-based system of demographic and social statistics in Denmark. Stat J Un Econ Comm Eur 1995;12:49—55.

20.

Galobardes B. , Shaw M. , Lawlor DA , Lynch JW , Davey SG Indicators of socioeconomic position (Part 1). J Epidemiol Community Health 2006;60:7—12.

21.

SAS/Stat Software , Changes and enhancements. Cary, NC: SAS Institute; 1996.

22.

Harlan WR , Sandler SA , Lee KL , Lam LC , Mark DB Importance of baseline functional and socioeconomic factors for participation in cardiac rehabilitation . Am J Cardiol 1995;76:36—9.

23.

Jackson R. , Chambless LE , Yang K. , Byrne T. , Watson R. , Folsom A. , et al. Differences between respondents and nonrespondents in a multicenter community-based study vary by gender ethnicity: The Atherosclerosis Risk In Communities (Aric) Study Investigators. J Clin Epidemiol 1996;49:1441—6.

24.

Sonne-Holm S. , Sorensen TI , Jensen G. , Schnohr P. Influence Of fatness, intelligence, education and sociodemographic factors on response rate in a health survey. J Epidemiol Community Health 1989;43:369—74.

25.

Lerman Y. , Shemer J. Epidemiologic characteristics of participants and nonparticipants in health-promotion programs. J Occup Environ Med 1996;38:535—8.

26.

Jacomb PA , Jorm AF , Korten AE , Christensen H. , Henderson AS

Predictors of refusal to participate: a longitudinal health survey of the elderly in Australia. BMC

Public Health 2002;2:4.

27.

Lagerlund M. , Sparen P. , Thurfjell E. , Ekbom A. , Lambe M. Predictors of non-attendance in a population-based mammography screening programme: socio-demographic factors and aspects of health behaviour. Eur J Cancer Prev 2000;9:25—33.

28.

Lagerlund M. , Maxwell AE , Bastani R. , Thurfjell E. , Ekbom A. , Lambe M. Sociodemographic predictors of non-attendance at invitational mammography screening—a population-based register study (Sweden). Cancer Causes Control 2002;13:73—82.

29.

Bergstrand R. , Vedin A. , Wilhelmsson C. , Wilhelmsen L. Bias due to non-participation and heterogenous sub-groups in population surveys. J Chronic Dis 1983;36:725—8.

30.

Walker M. , Shaper AG , Cook DG Non-participation and mortality in a prospective study of cardiovascular disease . J Epidemiol Community Health 1987;41:295—9.

31.

Hennekens CH , Buring JE , Mayrent SL , editors. Epidemiology in medicine. 1st ed. Boston and Toronto : Little, Brown; 1987.

32.

Rothman KJ , Greenland S , editors. Modern epidemiology. 2nd ed. Philadelphia: Lippincott-Raven; 1998.

33.

Levnedsmiddelstyrelsen. Food Consumption of the Danish Population 1995: The main results. Denmark: Levnedsmiddelstyrelsen; 1996 (in Danish).