Journal of Preventive Medicine and Public Health

The Korean Society for Preventive Medicine (대한예방의학회)
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Strengthening Causal Inference in Studies using Non-experimental Data: An Application of Propensity Score and Instrumental Variable Methods

비실험자료를 이용한 연구에서 인과적 추론의 강화: 성향점수와 도구변수 방법의 적용

  • Kim, Myoung-Hee (Department of Preventive Medicine, Eulji University College of Medicine) ;
  • Do, Young-Kyung (Department of Health Policy and Administration, University of North Carolina at Chapel Hill School of Public Health)
  • 김명희 (을지의과대학교 예방의학교실) ;
  • 도영경 (노스캐롤라이나대 보건대학원 보건정책관리학과)
  • Published : 2007.11.30
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Abstract

Objectives : This study attempts to show how studies using non-experimental data can strengthen causal inferences by applying propensity score and instrumental variable methods based on the counterfactual framework. For illustrative purposes, we examine the effect of having private health insurance on the probability of experiencing at least one hospital admission in the previous year. Methods : Using data from the 4th wave of the Korea Labor and Income Panel Study, we compared the results obtained using propensity score and instrumental variable methods with those from conventional logistic and linear regression models, respectively. Results : While conventional multiple regression analyses fail to identify the effect, the results estimated using propensity score and instrumental variable methods suggest that having private health insurance has positive and statistically significant effects on hospital admission. Conclusions : This study demonstrates that propensity score and instrumental variable methods provide potentially useful alternatives to conventional regression approaches in making causal inferences using non-experimental data.

Keywords

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