1Rosenbaum PR,Rubin DB.Reducing bias in observational studies using subclassification on the propensity score[J].J Am Star Assoc,1984,79:516-524.
2Rosenbaum PR,Rubin DB.The central role of the propensity score in observational studies for causal effects[J].Biometrika,1983,70,41-55.
3D' Agostino RB.Propensity score methods for bias reduction in the comparison of a treatment to a non-randomized control group[J].Stat Med,1998,1-7:2265-2281.
4Frigoletto FD,Iieberman E,Lang JM.,et al.A clinical trial of active management of labor[J].N Engl J Med,1995,333:745-750.
5Iieberman E,Lang JM,Cohen A,et al.Association of epidural analgesia with caesareans in nulliparous women[J].Obstet Gynecol,1996,88:993-1000.
6Glynn RJ,Schneeweiss S,Wang PS,et al.Selective prescribing led to overestimation of the benefits of lipid-lowering drugs[J].J Clin Epidemiol,2006,59:819-828.
7Cochran WG.The effectiveness of adjustment by subclassification in removing bias in observational studies[J].Biometrics,1968,24:205-213.
8Rubin D B.Using multivariate matched sampling and regression adjustment to control bias in observational studies[J].J Am Stat As-soc,1979,74:318-324.
7Parsons LS,Ovation Research Group,Seattle,WA.Reducing bias in a propensity score matched-pair sample using greedy matching techniques[EB/OL].http://www2.sas.com/proceedings/sugi26/p214-26.pdf.2010-9-22.
