title: Clinical genetic research 1: Bias.
abstract: Clinical epidemiological research in genetic diseases entails assessment of phenotypes, the burden and etiology of disease, and the efficacy of preventive measures or treatments in populations. In all areas, the main focus is to describe the relationship between exposure and outcome and to determine one of the following: prevalence, incidence, cause, prognosis, or effect of treatment. The accuracy of these conclusions is determined by the validity of the study. Validity is determined by addressing potential biases and possible confounders that may be responsible for the observed association. Therefore, it is important to understand the types of bias that exist and also to be able to assess their impact on the magnitude and direction of the observed effect. The following chapter reviews the epidemiological concepts of selection bias, information bias, and confounding and discusses ways in which these sources of bias can be minimized.
authors.affiliation: Health Science Centre, Memorial University of Newfoundland, Room 4M129, 300 Prince Philip Drive, St. John's, NL, Canada, A1B 3V6, c45sns@mun.ca.
authors.forename: Susan
authors.initials: S
authors.lastname: Stuckless
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Parfrey
mesh_terms: D015982:Bias; D035843:Biomedical Research / Q000379:methods*; D016021:Epidemiologic Studies; D036281:Genetic Research; D006801:Humans