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Inverse Probability of Treatment Weighting Propensity Score using the Military Health System Data Repository and National Death Index
Published on: January 8, 2020
Propensity Score Methods for Bias Reduction in Observational Studies of Treatment Effect
Sindhu R Johnson1, George A Tomlinson2, Gillian A Hawker3
1Division of Rheumatology, Department of Medicine, Toronto Western Hospital, Mount Sinai Hospital, Ground Floor, East Wing, 399 Bathurst Street, Toronto, Ontario M5T 2S8, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, 155 College Street, Toronto, Ontario M5T 3M6, Canada.
Abstract:
A challenge to the use of observational data to study treatment effects is the issue of confounding. Noncomparability of exposed and nonexposed subjects can lead to biased estimation of the treatment effect. The propensity score is a balancing score that can be used to form matched groups, or pairs, that are not systematically different and enable nonbiased comparisons between groups. This article reviews propensity score methods with an illustrative example of the application of propensity score matching in an observational study of an uncommon disease (systemic sclerosis).
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