title: [Three types of bias: distortion of research results and how that can be prevented].
abstract: A systematic distortion of the relationship between a treatment, risk factor or exposure and clinical outcomes is denoted by the term 'bias'. Three types of bias can be distinguished: information bias, selection bias, and confounding. These three types of bias and their potential solutions are discussed using various examples.
authors.affiliation: Universitair Medisch Centrum Utrecht, Julius Centrum voor Gezondheidswetenschappen en Eerstelijns Geneeskunde, Utrecht.
authors.forename: Rolf H H
authors.initials: RH
authors.lastname: Groenwold
mesh_terms: D015982:Bias; D035843:Biomedical Research / Q000592:standards*; D003627:Data Interpretation, Statistical; D006801:Humans; D012307:Risk Factors; D015983:Selection Bias