title: Understanding logistic regression analysis through example.
abstract: Logistic regression is a valuable statistical tool that is often used in primary care research. When researchers explore the association between a possible risk factor and a disease, they attempt to control the effects of extraneous factors (confounders) that can obscure the true association. Using logistic regression, researchers can simultaneously control for the effects of multiple confounders. When investigators use logistic regression, they make subjective decisions about which factors to include in the analysis and in the final predictive model. Critical readers must understand basic concepts of logistic regression and potential problems with its use before they can accurately interpret study results. This article uses a familiar example to explain the principles of logistic regression to make it understandable to nonstatisticians.
authors.affiliation: Department of Family Practice, University of Iowa Hospitals and Clinics, Iowa City, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Ely
authors.forename: J D
authors.initials: JD
authors.lastname: Dawson
authors.forename: D R
authors.initials: DR
authors.lastname: Mehr
authors.forename: T L
authors.initials: TL
authors.lastname: Burns
mesh_terms: D003069:Coffee / Q000009:adverse effects; D003327:Coronary Disease / Q000453:epidemiology / Q000209:etiology; D003627:Data Interpretation, Statistical; D005194:Family Practice / Q000193:education*; D006801:Humans; D015233:Models, Statistical; D011320:Primary Health Care / Q000706:statistics & numerical data*; D012044:Regression Analysis; D012306:Risk
chemical_list: D003069:Coffee