Is Opium a Real Risk Factor for Esophageal Cancer or Just a Methodological Artifact? Hospital and Neighborhood Controls in Case-Control Studies

DSpace/Manakin Repository

Is Opium a Real Risk Factor for Esophageal Cancer or Just a Methodological Artifact? Hospital and Neighborhood Controls in Case-Control Studies

Show simple item record

dc.contributor.author Shakeri, Ramin
dc.contributor.author Kamangar, Farin
dc.contributor.author Nasrollahzadeh, Dariush
dc.contributor.author Nouraie, Mehdi
dc.contributor.author Khademi, Hooman
dc.contributor.author Etemadi, Arash
dc.contributor.author Islami, Farhad
dc.contributor.author Marjani, Hajiamin
dc.contributor.author Fahimi, Saman
dc.contributor.author Sepehr, Alireza
dc.contributor.author Rahmati, Atieh
dc.contributor.author Brennan, Paul
dc.contributor.author Boffetta, Paolo
dc.contributor.author Malekzadeh, Reza
dc.contributor.author Majdzadeh, Reza
dc.contributor.author Abnet, Christian C.
dc.contributor.author Dawsey, Sanford M.
dc.date.accessioned 2012-10-09T01:43:05Z
dc.date.issued 2012
dc.identifier.citation Shakeri, Ramin, Farin Kamangar, Dariush Nasrollahzadeh, Mehdi Nouraie, Hooman Khademi, Arash Etemadi, Farhad Islami, et al. 2012. Is opium a real risk factor for esophageal cancer or just a methodological artifact? Hospital and neighborhood controls in case-control studies. PLoS ONE 7(3): e32711. en_US
dc.identifier.issn 1932-6203 en_US
dc.identifier.uri http://nrs.harvard.edu/urn-3:HUL.InstRepos:9696332
dc.description.abstract Background: Control selection is a major challenge in epidemiologic case-control studies. The aim of our study was to evaluate using hospital versus neighborhood control groups in studying risk factors of esophageal squamous cell carcinoma (ESCC). Methodology/Principal Findings: We compared the results of two different case-control studies of ESCC conducted in the same region by a single research group. Case definition and enrollment were the same in the two studies, but control selection differed. In the first study, we selected two age- and sex-matched controls from inpatient subjects in hospitals, while for the second we selected two age- and sex-matched controls from each subject's neighborhood of residence. We used the test of heterogeneity to compare the results of the two studies. We found no significant differences in exposure data for tobacco-related variables such as cigarette smoking, chewing Nass (a tobacco product) and hookah (water pipe) usage, but the frequency of opium usage was significantly different between hospital and neighborhood controls. Consequently, the inference drawn for the association between ESCC and tobacco use did not differ between the studies, but it did for opium use. In the study using neighborhood controls, opium use was associated with a significantly increased risk of ESCC (adjusted OR 1.77, 95% CI 1.17–2.68), while in the study using hospital controls, this was not the case (OR 1.09, 95% CI 0.63–1.87). Comparing the prevalence of opium consumption in the two control groups and a cohort enrolled from the same geographic area suggested that the neighborhood controls were more representative of the study base population for this exposure. Conclusions/Significance: Hospital and neighborhood controls did not lead us to the same conclusion for a major hypothesized risk factor for ESCC in this population. Our results show that control group selection is critical in drawing appropriate conclusions in observational studies. en_US
dc.language.iso en_US en_US
dc.publisher Public Library of Science en_US
dc.relation.isversionof doi:10.1371/journal.pone.0032711 en_US
dc.relation.hasversion http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3291619/pdf/ en_US
dash.license LAA
dc.title Is Opium a Real Risk Factor for Esophageal Cancer or Just a Methodological Artifact? Hospital and Neighborhood Controls in Case-Control Studies en_US
dc.type Journal Article en_US
dc.description.version Version of Record en_US
dc.relation.journal PLoS ONE en_US
dash.depositing.author Sepehr, Alireza
dc.date.available 2012-10-09T01:43:05Z

Files in this item

Files Size Format View
3291619.pdf 97.48Kb PDF View/Open

This item appears in the following Collection(s)

Show simple item record

 
 

Search DASH


Advanced Search
 
 

Submitters