RT Journal Article
SR Electronic
T1 Non-participant characteristics and the association between socioeconomic factors and brain tumour risk
JF Journal of Epidemiology and Community Health
JO J Epidemiol Community Health
FD BMJ Publishing Group Ltd
SP 736
OP 743
DO 10.1136/jech.2008.085845
VO 64
IS 8
A1 Annette Wigertz
A1 Stefan Lönn
A1 Per Hall
A1 Maria Feychting
YR 2010
UL http://jech.bmj.com/content/64/8/736.abstract
AB Background The aim of the study was to identify demographic and socioeconomic characteristics of participants and non-participants in a Swedish population-based case-control study on brain tumours and to analyse the association between socioeconomic factors and glioma and meningioma risk.Methods Record linkage was made to an official register to gather information on socioeconomic status, income, education and demography for all participating and non-participating cases and controls.Results 494 glioma cases, 321 meningioma cases and 955 controls were eligible and 74%, 85% and 70%, respectively, participated. Working status and income level were positively associated with participation among cases and controls. Among both cases and controls, being married, and having a high education were also associated with participation. Having a family income level in the highest quartile was associated with an increased glioma risk (OR 1.5, 95% CI 1.1 to 2.1). This risk increase diminished when only participating individuals were included in the analysis. Socioeconomic factors were not associated with meningioma risk.Conclusions Non-participation, related to socioeconomic factors, is a potential source of bias in case-control studies that should be acknowledged; however, the effect was not large in the present study due to the fact that the level of participation was comparable between cases and controls and participation was similarly influenced by socioeconomic factors among cases and controls. The association between a high income level and an increased glioma risk and possible underlying factors needs to be explored further.