title: Analyzing GeoSentinel surveillance data: a comparison of methods to explore acute gastrointestinal illness among international travelers.
abstract: GeoSentinel is a global surveillance network of travel medicine clinics that collect data from ill international travelers. Analyses have relied on proportionate morbidity calculations, but proportionate morbidity cannot estimate disease risk because healthy travelers are not included in the denominator. The authors evaluated the use of a case-control design, controlling for GeoSentinel site and date of clinic visit, to calculate a reporting odds ratio (ROR). The association between region of travel and acute gastrointestinal illness was evaluated. All analyses found that the association with acute gastrointestinal illness was greatest among those who traveled to North Africa and South-Central Asia. There was consistency in the magnitude of the ROR and proportionate morbidity ratio (PMR) in regions such as the Caribbean. However, in other regions, the matched ROR was noticeably different than the PMR. The case-control ROR may be preferred for single-disease/syndrome analytical studies using GeoSentinel surveillance data or other surveillance data.
authors.affiliation: Department of Epidemiology, Rollins School of Public Health and Laney Graduate School, Emory University, Atlanta.
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Mues
authors.forename: Douglas H
authors.initials: DH
authors.lastname: Esposito
authors.forename: Pauline V
authors.initials: PV
authors.lastname: Han
authors.forename: Emily S
authors.initials: ES
authors.lastname: Jentes
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Sotir
authors.forename: Clive
authors.initials: C
authors.lastname: Brown
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D062665:Epidemiological Monitoring; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology*; D005843:Geography; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D018570:Risk Assessment; D014195:Travel; D057236:Travel Medicine / Q000379:methods*; D055815:Young Adult
keywords: case-control studies; control groups; gastrointestinal diseases; sentinel surveillance; travel