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Review
. 2023 Apr;38(4):622-626.
doi: 10.1016/j.arth.2022.08.030. Epub 2023 Jan 11.

Propensity Scores: Confounder Adjustment When Comparing Nonrandomized Groups in Orthopaedic Surgery

Dirk R Larson  1 , Isabella Zaniletti  2 , David G Lewallen  3 , Daniel J Berry  3 , Hilal Maradit Kremers  4
Affiliations
Review

Propensity Scores: Confounder Adjustment When Comparing Nonrandomized Groups in Orthopaedic Surgery

Dirk R Larson et al. J Arthroplasty. 2023 Apr.

Abstract

Many studies in arthroplasty research are based on nonrandomized, retrospective, registry-based cohorts. In these types of studies, patients belonging to different treatment or exposure groups often differ with respect to patient characteristics, medical histories, surgical indications, or other factors. Consequently, comparisons of nonrandomized groups are often subject to treatment selection bias and confounding. Propensity scores can be used to balance cohort characteristics, thus helping to minimize potential bias and confounding. This article explains how propensity scores are created and describes multiple ways in which they can be applied in the analysis of nonrandomized studies. Please visit the following (https://www.youtube.com/watch?v=sqgxl_nZWS4&t=3s) for a video that explains the highlights of the paper in practical terms.

Keywords: bias; confounding; inverse probability of treatment; propensity score; statistics; total joint arthroplasty.

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Conflict of interest statement

One or more of the authors of this paper have disclosed potential or pertinent conflicts of interest, which may include receipt of payment, either direct or indirect, institutional support, or association with an entity in the biomedical field which may be perceived to have potential conflict of interest with this work. For full disclosure statements refer to https://doi.org/10.1016/j.arth.2022.08.030.

Figures

Fig. 1.
Fig. 1.
Standardized differences between patients before (solid triangles) and after (hollow dots) propensity score weighting.
See this image and copyright information in PMC

References

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