[Propensity score analysis in observational research: application to a study of prophylaxis against venous thromboembolism]

Rev Med Interne. 2008 Mar;29(3):255-8. doi: 10.1016/j.revmed.2007.08.001. Epub 2007 Sep 21.
[Article in French]

Abstract

Introduction: In observational studies, a significant difference in the outcomes between treated and untreated patients may be observed in absence of treatment effect and caused by differences in baseline characteristics.

Exegesis: Propensity score analysis is a post hoc adjustment method which consists in deriving the conditional probability of receiving the treatment for a patient given his measured baseline characteristics (i.e., the propensity score). Matching each treated patient to an untreated one who has the nearest propensity score tends to balance baseline characteristics between the two groups and reduce the risk for overt bias. Then, the outcomes can be compared between matched treated and untreated patients.

Conclusion: Propensity score analysis is relevant for clinical conditions and treatments for which randomized controlled trials are unlikely to be conducted. However, propensity analysis cannot adjust for unmeasured characteristics and sensitivity analysis should be performed to assess how sensitive the conclusions are to potential confounding factors.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Anticoagulants / administration & dosage
  • Anticoagulants / therapeutic use
  • Fibrinolytic Agents / administration & dosage
  • Fibrinolytic Agents / therapeutic use
  • Heparin, Low-Molecular-Weight / administration & dosage
  • Heparin, Low-Molecular-Weight / therapeutic use
  • Humans
  • Logistic Models
  • Models, Statistical*
  • Multicenter Studies as Topic
  • Multivariate Analysis
  • Observation*
  • Odds Ratio
  • ROC Curve
  • Randomized Controlled Trials as Topic
  • Time Factors
  • Treatment Outcome
  • Ultrasonography, Doppler
  • Venous Thromboembolism / diagnostic imaging
  • Venous Thromboembolism / drug therapy
  • Venous Thromboembolism / prevention & control*
  • Venous Thromboembolism / therapy

Substances

  • Anticoagulants
  • Fibrinolytic Agents
  • Heparin, Low-Molecular-Weight