• Dataset characteristics affected the performance of propensity score methods for controlling confounding: a simulation study

    Type Journal Article
    Author J. Wilkinson
    Author M. A. Mamas
    Author E. Kontopantelis
    URL https://www.jclinepi.com/article/S0895-4356(22)00230-X/fulltext?rss=yes
    Volume 0
    Issue 0
    Publication Journal of Clinical Epidemiology
    ISSN 0895-4356, 1878-5921
    Date 2022-09-17
    Extra Publisher: Elsevier PMID: 36126791
    Journal Abbr Journal of Clinical Epidemiology
    DOI 10.1016/j.jclinepi.2022.09.009
    Accessed 9/21/2022, 6:54:20 AM
    Library Catalog www.jclinepi.com
    Language English
    Abstract Objective In observational studies, researchers must select a method to control for confounding. Options include propensity score methods and regression. It remains unclear how dataset characteristics (size, overlap in propensity scores, exposure prevalence) influence the relative performance of the methods. Study Design A simulation study to evaluate the role of dataset characteristics on the performance of propensity score methods, compared to logistic regression, for estimating a marginal odds ratio was conducted. Dataset size, overlap in propensity scores, and exposure prevalence were varied. Results Regression showed poor coverage for small sample sizes, but with large sample sizes was relatively robust to imbalance in propensity scores and low exposure prevalence. Propensity score methods displayed suboptimal coverage as overlap in propensity scores decreased, which was exacerbated at larger sample sizes. Power of matching methods was particularly affected by lack of overlap, low exposure prevalence, and small sample size. The advantage of regression for large data size was reduced in sensitivity analysis with a complementary log-log outcome generation mechanism and unmeasured confounding, with superior bias and error but inferior coverage to matching methods. Conclusion Dataset characteristics influence performance of methods for confounder adjustment. In many scenarios, regression may be the preferable option.
    Short Title Dataset characteristics affected the performance of propensity score methods for controlling confounding
    Date Added 9/21/2022, 6:54:20 AM
    Modified 9/21/2022, 6:55:35 AM

    Tags:

    • covariable-adjustment
    • propensity

    Attachments

    • PubMed entry
  • On the inconsistency of matching without replacement

    Type Journal Article
    Author Fredrik Sävje
    URL https://doi.org/10.1093/biomet/asab035
    Issue asab035
    Publication Biometrika
    ISSN 0006-3444
    Date June 22, 2021
    Journal Abbr Biometrika
    DOI 10.1093/biomet/asab035
    Accessed 6/23/2021, 4:44:03 PM
    Library Catalog Silverchair
    Abstract The paper shows that matching without replacement on propensity scores produces estimators that generally are inconsistent for the average treatment effect of the treated. To achieve consistency, practitioners must either assume that no units exist with propensity scores greater than one-half or assume that there is no confounding among such units. The result is not driven by the use of propensity scores, and similar artifacts arise when matching on other scores as long as it is without replacement.
    Date Added 6/23/2021, 4:44:03 PM
    Modified 6/23/2021, 4:44:28 PM

    Tags:

    • matching
    • propensity
  • Comparison of Propensity Score Methods and Covariate Adjustment: Evaluation in 4 Cardiovascular Studies

    Type Journal Article
    Author Markus C. Elze
    Author John Gregson
    Author Usman Baber
    Author Elizabeth Williamson
    Author Samantha Sartori
    Author Roxana Mehran
    Author Melissa Nichols
    Author Gregg W. Stone
    Author Stuart J. Pocock
    URL https://www.sciencedirect.com/science/article/pii/S073510971637036X
    Volume 69
    Issue 3
    Pages 345-357
    Publication Journal of the American College of Cardiology
    ISSN 0735-1097
    Date January 24, 2017
    Journal Abbr Journal of the American College of Cardiology
    DOI 10.1016/j.jacc.2016.10.060
    Accessed 3/1/2021, 4:08:01 PM
    Library Catalog ScienceDirect
    Language en
    Abstract Propensity scores (PS) are an increasingly popular method to adjust for confounding in observational studies. Propensity score methods have theoretical advantages over conventional covariate adjustment, but their relative performance in real-word scenarios is poorly characterized. We used datasets from 4 large-scale cardiovascular observational studies (PROMETHEUS, ADAPT-DES [the Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents], THIN [The Health Improvement Network], and CHARM [Candesartan in Heart Failure-Assessment of Reduction in Mortality and Morbidity]) to compare the performance of conventional covariate adjustment with 4 common PS methods: matching, stratification, inverse probability weighting, and use of PS as a covariate. We found that stratification performed poorly with few outcome events, and inverse probability weighting gave imprecise estimates of treatment effect and undue influence to a small number of observations when substantial confounding was present. Covariate adjustment and matching performed well in all of our examples, although matching tended to give less precise estimates in some cases. PS methods are not necessarily superior to conventional covariate adjustment, and care should be taken to select the most suitable method.
    Short Title Comparison of Propensity Score Methods and Covariate Adjustment
    Date Added 3/1/2021, 4:08:01 PM
    Modified 3/1/2021, 4:20:40 PM

    Tags:

    • matching
    • covariate-adjustment
    • propensity
    • stratification
  • Stratification for the propensity score compared with linear regression techniques to assess the effect of treatment or exposure

    Type Journal Article
    Author Stephen Senn
    Author Erika Graf
    Author Angelika Caputo
    Volume 26
    Pages 5529-5544
    Publication Stat Med
    Date 2007
    Extra Citation Key: sen07str tex.citeulike-article-id= 13265650 tex.posted-at= 2014-07-14 14:10:01 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 1/19/2021, 8:03:32 AM

    Tags:

    • confounding
    • propensity-score
    • conditional-vs-marginal-independence
    • linear-models

    Notes:

    • propensity adjustment puts all emphasis on bias at the cost of variance

  • Propensity scores using missingness pattern information: a practical guide

    Type Journal Article
    Author Helen A. Blake
    Author Clémence Leyrat
    Author Kathryn E. Mansfield
    Author Shaun Seaman
    Author Laurie A. Tomlinson
    Author James Carpenter
    Author Elizabeth J. Williamson
    URL https://onlinelibrary.wiley.com/doi/abs/10.1002/sim.8503
    Rights © 2020 John Wiley & Sons, Ltd.
    Volume n/a
    Issue n/a
    Publication Statistics in Medicine
    ISSN 1097-0258
    Date 2020
    Extra _eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1002/sim.8503
    DOI 10.1002/sim.8503
    Accessed 2/28/2020, 4:02:36 PM
    Library Catalog Wiley Online Library
    Language en
    Abstract Electronic health records are a valuable data source for investigating health-related questions, and propensity score analysis has become an increasingly popular approach to address confounding bias in such investigations. However, because electronic health records are typically routinely recorded as part of standard clinical care, there are often missing values, particularly for potential confounders. In our motivating study—using electronic health records to investigate the effect of renin-angiotensin system blockers on the risk of acute kidney injury—two key confounders, ethnicity and chronic kidney disease stage, have 59% and 53% missing data, respectively. The missingness pattern approach (MPA), a variant of the missing indicator approach, has been proposed as a method for handling partially observed confounders in propensity score analysis. In the MPA, propensity scores are estimated separately for each missingness pattern present in the data. Although the assumptions underlying the validity of the MPA are stated in the literature, it can be difficult in practice to assess their plausibility. In this article, we explore the MPA's underlying assumptions by using causal diagrams to assess their plausibility in a range of simple scenarios, drawing general conclusions about situations in which they are likely to be violated. We present a framework providing practical guidance for assessing whether the MPA's assumptions are plausible in a particular setting and thus deciding when the MPA is appropriate. We apply our framework to our motivating study, showing that the MPA's underlying assumptions appear reasonable, and we demonstrate the application of MPA to this study.
    Short Title Propensity scores using missingness pattern information
    Date Added 2/28/2020, 4:02:36 PM
    Modified 2/28/2020, 4:03:14 PM

    Tags:

    • imputation
    • propensity
    • missing
  • The Central Role of Bayes’ Theorem for Joint Estimation of Causal Effects and Propensity Scores

    Type Journal Article
    Author Corwin Matthew Zigler
    URL https://doi.org/10.1080/00031305.2015.1111260
    Volume 70
    Issue 1
    Pages 47-54
    Publication The American Statistician
    ISSN 0003-1305
    Date January 2, 2016
    Extra PMID: 27482121
    DOI 10.1080/00031305.2015.1111260
    Accessed 11/25/2019, 7:36:13 AM
    Library Catalog Taylor and Francis+NEJM
    Abstract Although propensity scores have been central to the estimation of causal effects for over 30 years, only recently has the statistical literature begun to consider in detail methods for Bayesian estimation of propensity scores and causal effects. Underlying this recent body of literature on Bayesian propensity score estimation is an implicit discordance between the goal of the propensity score and the use of Bayes’ theorem. The propensity score condenses multivariate covariate information into a scalar to allow estimation of causal effects without specifying a model for how each covariate relates to the outcome. Avoiding specification of a detailed model for the outcome response surface is valuable for robust estimation of causal effects, but this strategy is at odds with the use of Bayes’ theorem, which presupposes a full probability model for the observed data that adheres to the likelihood principle. The goal of this article is to explicate this fundamental feature of Bayesian estimation of causal effects with propensity scores to provide context for the existing literature and for future work on this important topic.[Received June 2014. Revised September 2015.]
    Date Added 11/25/2019, 7:36:13 AM
    Modified 11/25/2019, 7:37:12 AM

    Tags:

    • bayes
    • causal-inference
    • propensity
    • causality
  • Propensity score methods gave similar results to traditional regression modeling in observational studies: a systematic review

    Type Journal Article
    Author Baiju R. Shah
    Author Andreas Laupacis
    Author Janet E. Hux
    Author Peter C. Austin
    Volume 58
    Pages 550-559
    Publication J Clin Epi
    Date 2005
    Extra Citation Key: sha05pro tex.citeulike-article-id= 13265415 tex.posted-at= 2014-07-14 14:09:56 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score

    Notes:

    • "Propensity scores gave slightly weaker associations; however many of the reviewed studies did not implement propensity scores well.";e.g. many papers tried to be parsimoneous in the propensity model

  • Variable selection and raking in propensity scoring

    Type Journal Article
    Author David R. Judkins
    Author David Morganstein
    Author Paul Zador
    Author Andrea Piesse
    Author Brandon Barrett
    Author Pushpal Mukhopadhyay
    Volume 26
    Pages 1022-1033
    Publication Stat Med
    Date 2007
    Extra Citation Key: jud07var tex.citeulike-article-id= 13265561 tex.posted-at= 2014-07-14 14:09:59 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • causal-inference
    • calibration
    • health-communication
    • program-evaluation

    Notes:

    • "articles dating back ... have pointed to situations where variance reduction can be achieved by making the models richer than strictly required to achieve bias elimination. In practice, this suggests a double benefit to overfitting in that both the risk of bias and variance are made smaller. We show that this double benefit is available only when the number of potential covariates is small relative to the sample size and when the covariates are related to outcomes.";ordinal treatment intensity modeled with ordinal logistic model;overfitting of the propensity model is beneficial if the extra variables are correlated with the outcome;if there are "only 10 cases per available covariate, dramatic overfitting can easily occur that will rob the analysis of all power to detect effects";polytomous model when PO violated;raking requires large sample sizes and categorical covariates

  • The prognostic analogue of the propensity score

    Type Journal Article
    Author Ben B. Hansen
    Volume 95
    Pages 481-488
    Publication Biometrika
    Date 2008
    Extra Citation Key: han08pro tex.citeulike-article-id= 13265679 tex.posted-at= 2014-07-14 14:10:01 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-study
    • propensity-score
    • matching
    • covariate-balance
    • matched-sampling
    • prognostic-score
    • quasi-experiment
    • regression-discontinuity
    • subclassification

    Notes:

    • prognostic score (Miettinen multivariate confounder score) is especially prone to overfitting;problems with same sample estimation

  • Bayesian propensity score analysis for observational data

    Type Journal Article
    Author Lawrence C. McCandless
    Author Paul Gustafson
    Author Peter C. Austin
    Volume 28
    Pages 94-112
    Publication Stat Med
    Date 2009
    Extra Citation Key: mcc09bay tex.citeulike-article-id= 13265723 tex.posted-at= 2014-07-14 14:10:02 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • observational-study
    • propensity-score
    • bias
    • causal-inference
    • bayesian-statistics

    Notes:

    • using Bayesian credible intervals to adjust for uncertainty in estimation of propensity score;relied heavily on Rubin 5-category propensity adjustment

  • The control of confounding by intermediate variables

    Type Journal Article
    Author James Robins
    Volume 8
    Pages 679-701
    Publication Stat Med
    Date 1989
    Extra Citation Key: rob89con tex.citeulike-article-id= 13264738 tex.posted-at= 2014-07-14 14:09:41 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
    • dynamic-propensity-score
    • time-dependent-treatment
  • Assessing sensitivity to an unobserved binary covariate in an observational study with binary outcome

    Type Journal Article
    Author Paul R. Rosenbaum
    Author Donald B. Rubin
    Volume 45
    Pages 212-218
    Publication J Roy Stat Soc B
    Date 1983
    Extra Citation Key: ros83ass tex.citeulike-article-id= 13264750 tex.posted-at= 2014-07-14 14:09:41 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
    • cabg
    • duke-data
    • sensitivity-analysis
    • treatment-by-indication
  • The central role of the propensity score in observational studies for causal effects

    Type Journal Article
    Author P. R. Rosenbaum
    Author D. Rubin
    Volume 70
    Pages 41-55
    Publication Biometrika
    Date 1983
    Extra Citation Key: ros83cen tex.citeulike-article-id= 13264751 tex.posted-at= 2014-07-14 14:09:41 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
  • Constructing a control group using multivariate matched sampling methods that incorporate the propensity score

    Type Journal Article
    Author Paul R. Rosenbaum
    Author Donald B. Rubin
    Volume 39
    Pages 33-38
    Publication Am Statistician
    Date 1985
    Extra Citation Key: ros85con tex.citeulike-article-id= 13264754 tex.posted-at= 2014-07-14 14:09:41 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
    • bias
    • matching
  • Estimating exposure effects by modeling the expectation of exposure conditional on confounders

    Type Journal Article
    Author James M. Robins
    Author Steven D. Mark
    Author Whitney K. Newey
    Volume 48
    Pages 479-495
    Publication Biometrics
    Date 1992
    Extra Citation Key: rob92esti tex.citeulike-article-id= 13264741 tex.posted-at= 2014-07-14 14:09:41 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
    • causality
    • continuous-exposure
  • Observational Studies

    Type Book
    Author Paul R. Rosenbaum
    Place New York
    Publisher Springer-Verlag
    Date 1995
    Extra Citation Key: ros95obs tex.citeulike-article-id= 13264762 tex.posted-at= 2014-07-14 14:09:41 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • observational-studies
    • see-gre96rev
  • Matching using estimated propensity scores: Relating theory to practice

    Type Journal Article
    Author Donald B. Rubin
    Author Neal Thomas
    Volume 52
    Pages 249-264
    Publication Biometrics
    Date 1996
    Extra Citation Key: rub96mat tex.citeulike-article-id= 13264778 tex.posted-at= 2014-07-14 14:09:42 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
  • Estimating causal effects from a large data set using the propensity score

    Type Journal Article
    Author Donald B. Rubin
    Volume 127
    Pages 757-763
    Publication Ann Int Med
    Date 1997
    Extra Citation Key: rub97est tex.citeulike-article-id= 13264779 tex.posted-at= 2014-07-14 14:09:42 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • teaching-mds
    • observational-study
    • propensity-score
    • causal-inference
  • Ordering an echocardiogram for evaluation of left ventricular function: Level of expertise necessary for efficient use

    Type Journal Article
    Author J. Peter Weiss
    Author Carol Gruver
    Author Sanjiv Kaul
    Author Frank E. Harrell
    Author Jiri Sklenar
    Author John M. Dent
    Volume 13
    Pages 124-130
    Publication J Am Soc Echocard
    Date 2000
    Extra Citation Key: wei00ord tex.citeulike-article-id= 13265113 tex.posted-at= 2014-07-14 14:09:49 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • diagnosis
    • propensity-score
    • testing
    • used-design-library
  • Propensity score estimation: neural networks, support vector machines, decision trees (CART), and meta-classifiers as alternatives to logistic regression

    Type Journal Article
    Author Daniel Westreich
    Author Justin Lessler
    Author Michele J. Funk
    Volume 63
    Pages 826-833
    Publication J Clin Epi
    Date 2010
    Extra Citation Key: wes10pro tex.citeulike-article-id= 13265826 tex.posted-at= 2014-07-14 14:10:05 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • neural-networks
    • logistic-regression
    • review
    • recursive-partitioning
    • propensity-scores

    Notes:

    • use of more advanced predictive methods in developing propensity scores

  • Data Analysis Using Regression and Multilevel/Hierarchical Models

    Type Book
    Author Andrew Gelman
    Author Jennifer Hill
    URL http://www.amazon.com/exec/obidos/redirect?tag=citeulike07-20&path=ASIN/052168689X
    Edition 1
    Publisher Cambridge University Press
    ISBN 0-521-68689-X
    Date 2006-12
    Extra Citation Key: gel06dat tex.citeulike-article-id= 1334704 tex.citeulike-linkout-0= http://www.amazon.ca/exec/obidos/redirect?tag=citeulike09-20&path=ASIN/052168689X tex.citeulike-linkout-1= http://www.amazon.de/exec/obidos/redirect?tag=citeulike01-21&path=ASIN/052168689X tex.citeulike-linkout-2= http://www.amazon.fr/exec/obidos/redirect?tag=citeulike06-21&path=ASIN/052168689X tex.citeulike-linkout-3= http://www.amazon.jp/exec/obidos/ASIN/052168689X tex.citeulike-linkout-4= http://www.amazon.co.uk/exec/obidos/ASIN/052168689X/citeulike00-21 tex.citeulike-linkout-5= http://www.amazon.com/exec/obidos/redirect?tag=citeulike07-20&path=ASIN/052168689X tex.citeulike-linkout-6= http://www.worldcat.org/isbn/052168689X tex.citeulike-linkout-7= http://books.google.com/books?vid=ISBN052168689X tex.citeulike-linkout-8= http://www.amazon.com/gp/search?keywords=052168689X&index=books&linkCode=qs tex.citeulike-linkout-9= http://www.librarything.com/isbn/052168689X tex.day= 18 tex.howpublished= Paperback tex.posted-at= 2016-12-04 21:00:49 tex.priority= 2
    Abstract Data Analysis Using Regression and Multilevel/Hierarchical Models is a comprehensive manual for the applied researcher who wants to perform data analysis using linear and nonlinear regression and multilevel models. The book introduces a wide variety of models, whilst at the same time instructing the reader in how to fit these models using available software packages. The book illustrates the concepts by working through scores of real data examples that have arisen from the authors’ own applied research, with programming codes provided for each one. Topics covered include causal inference, including regression, poststratification, matching, regression discontinuity, and instrumental variables, as well as multilevel logistic regression and missing-data imputation. Practical tips regarding building, fitting, and understanding are provided throughout.
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • hierarchical-model
    • propensity-score
    • causal-inference
  • Comparing the performance of propensity score methods in healthcare database studies with rare outcomes

    Type Journal Article
    Author Jessica M. Franklin
    Author Wesley Eddings
    Author Peter C. Austin
    Author Elizabeth A. Stuart
    Author Sebastian Schneeweiss
    URL http://dx.doi.org/10.1002/sim.7250
    Pages n/a
    Publication Stat Med
    Date 2017-01
    Extra Citation Key: fra17com tex.citeulike-article-id= 14281729 tex.citeulike-attachment-1= fra17com.pdf; /pdf/user/harrelfe/article/14281729/1102672/fra17com.pdf; 1f5fe6204e1398690f6b3f39020f8561d32247ad tex.citeulike-linkout-0= http://dx.doi.org/10.1002/sim.7250 tex.day= 1 tex.posted-at= 2017-02-17 13:30:43 tex.priority= 2
    DOI 10.1002/sim.7250
    Abstract Nonrandomized studies of treatments from electronic healthcare databases are critical for producing the evidence necessary to making informed treatment decisions, but often rely on comparing rates of events observed in a small number of patients. In addition, studies constructed from electronic healthcare databases, for example, administrative claims data, often adjust for many, possibly hundreds, of potential confounders. Despite the importance of maximizing efficiency when there are many confounders and few observed outcome events, there has been relatively little research on the relative performance of different propensity score methods in this context. In this paper, we compare a wide variety of propensity-based estimators of the marginal relative risk. In contrast to prior research that has focused on specific statistical methods in isolation of other analytic choices, we instead consider a method to be defined by the complete multistep process from propensity score modeling to final treatment effect estimation. Propensity score model estimation methods considered include ordinary logistic regression, Bayesian logistic regression, lasso, and boosted regression trees. Methods for utilizing the propensity score include pair matching, full matching, decile strata, fine strata, regression adjustment using one or two nonlinear splines, inverse propensity weighting, and matching weights. We evaluate methods via a 'plasmode' simulation study, which creates simulated datasets on the basis of a real cohort study of two treatments constructed from administrative claims data. Our results suggest that regression adjustment and matching weights, regardless of the propensity score model estimation method, provide lower bias and mean squared error in the context of rare binary outcomes. Copyright 2017 John Wiley & Sons, Ltd.
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • covariable-adjustment
    • epub-replace

    Notes:

    • Included regression adjustment for spline of propensity in the comparison, which came out as co-winner with weighted matching.

  • Dealing with limited overlap in estimation of average treatment effects

    Type Journal Article
    Author Richard K. Crump
    Author V. Joseph Hotz
    Author Guido W. Imbens
    Author Oscar A. Mitnik
    URL http://dx.doi.org/10.1093/biomet/asn055
    Volume 96
    Issue 1
    Pages asn055-199
    Publication Biometrika
    ISSN 1464-3510
    Date 2009-01
    Extra Citation Key: cru09dea tex.citeulike-article-id= 4172464 tex.citeulike-attachment-1= cru09dea.pdf; /pdf/user/harrelfe/article/4172464/1001962/cru09dea.pdf; fa7879fde4385c8bca6f88002517ffcaac5e40d9 tex.citeulike-linkout-0= http://dx.doi.org/10.1093/biomet/asn055 tex.citeulike-linkout-1= http://biomet.oxfordjournals.org/content/96/1/187.abstract tex.citeulike-linkout-2= http://biomet.oxfordjournals.org/content/96/1/187.full.pdf tex.citeulike-linkout-3= http://www.ingentaconnect.com/content/oup/biomet/2009/00000096/00000001/art00014 tex.day= 24 tex.posted-at= 2015-01-22 13:53:54 tex.priority= 2 tex.publisher= Oxford University Press
    DOI 10.1093/biomet/asn055
    Abstract Estimation of average treatment effects under unconfounded or ignorable treatment assignment is often hampered by lack of overlap in the covariate distributions between treatment groups. This lack of overlap can lead to imprecise estimates, and can make commonly used estimators sensitive to the choice of specification. In such cases researchers have often used ad hoc methods for trimming the sample. We develop a systematic approach to addressing lack of overlap. We characterize optimal subsamples for which the average treatment effect can be estimated most precisely. Under some conditions, the optimal selection rules depend solely on the propensity score. For a wide range of distributions, a good approximation to the optimal rule is provided by the simple rule of thumb to discard all units with estimated propensity scores outside the range [0.1,0.9].
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
  • Regularized Regression Versus the High-Dimensional Propensity Score for Confounding Adjustment in Secondary Database Analyses.

    Type Journal Article
    Author Jessica M. Franklin
    Author Wesley Eddings
    Author Robert J. Glynn
    Author Sebastian Schneeweiss
    URL http://dx.doi.org/10.1093/aje/kwv108
    Volume 182
    Issue 7
    Pages 651-659
    Publication Am J Epi
    ISSN 1476-6256
    Date 2015-10
    Extra Citation Key: fra15reg tex.citeulike-article-id= 13898359 tex.citeulike-attachment-1= fra15reg.pdf; /pdf/user/harrelfe/article/13898359/1048898/fra15reg.pdf; 39307cda8e267a66c86bee376049380256c9fc8c tex.citeulike-linkout-0= http://dx.doi.org/10.1093/aje/kwv108 tex.citeulike-linkout-1= http://aje.oxfordjournals.org/content/early/2015/08/01/aje.kwv108.abstract tex.citeulike-linkout-2= http://aje.oxfordjournals.org/content/early/2015/08/01/aje.kwv108.full.pdf tex.citeulike-linkout-3= http://view.ncbi.nlm.nih.gov/pubmed/26233956 tex.citeulike-linkout-4= http://www.hubmed.org/display.cgi?uids=26233956 tex.day= 1 tex.pmid= 26233956 tex.posted-at= 2016-01-05 23:01:42 tex.priority= 0 tex.publisher= Oxford University Press
    DOI 10.1093/aje/kwv108
    Abstract Selection and measurement of confounders is critical for successful adjustment in nonrandomized studies. Although the principles behind confounder selection are now well established, variable selection for confounder adjustment remains a difficult problem in practice, particularly in secondary analyses of databases. We present a simulation study that compares the high-dimensional propensity score algorithm for variable selection with approaches that utilize direct adjustment for all potential confounders via regularized regression, including ridge regression and lasso regression. Simulations were based on 2 previously published pharmacoepidemiologic cohorts and used the plasmode simulation framework to create realistic simulated data sets with thousands of potential confounders. Performance of methods was evaluated with respect to bias and mean squared error of the estimated effects of a binary treatment. Simulation scenarios varied the true underlying outcome model, treatment effect, prevalence of exposure and outcome, and presence of unmeasured confounding. Across scenarios, high-dimensional propensity score approaches generally performed better than regularized regression approaches. However, including the variables selected by lasso regression in a regular propensity score model also performed well and may provide a promising alternative variable selection method. The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • simulation-setup
    • propensity-score
    • penalization

    Notes:

    • plasmode simulation; references Bross method of simultaneously scoring association with exposure, association with outcome, and prevalence

  • Too many covariates and too few cases? - a comparative study

    Type Journal Article
    Author Qingxia Chen
    Author Hui Nian
    Author Yuwei Zhu
    Author H. Keipp Talbot
    Author Marie R. Griffin
    Author Frank E. Harrell
    URL http://dx.doi.org/10.1002/sim.7021
    Volume 35
    Issue 25
    Pages 4546-4558
    Publication Stat Med
    ISSN 02776715
    Date 2016-11
    Extra Citation Key: che16too tex.citeulike-article-id= 14218257 tex.citeulike-attachment-1= che16too.pdf; /pdf/user/harrelfe/article/14218257/1093467/che16too.pdf; 3227b989b9dc8141aeff04faa3e49f67159e8358 tex.citeulike-linkout-0= http://dx.doi.org/10.1002/sim.7021 tex.day= 10 tex.posted-at= 2016-12-01 14:22:08 tex.priority= 2
    DOI 10.1002/sim.7021
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • penalized-estimation
    • propensity-score
    • covariate-adjustment
    • penalization
    • covariable-adjustment
    • penalized-mle
  • Propensity score model overfitting led to inflated variance of estimated odds ratios

    Type Journal Article
    Author Tibor Schuster
    Author Wilfrid K. Lowe
    Author Robert W. Platt
    URL http://dx.doi.org/10.1016/j.jclinepi.2016.05.017
    Publication J Clin Epi
    ISSN 08954356
    Date 2016-09
    Extra Citation Key: sch17pro tex.citeulike-article-id= 14220515 tex.citeulike-linkout-0= http://dx.doi.org/10.1016/j.jclinepi.2016.05.017 tex.posted-at= 2016-12-06 02:38:48 tex.priority= 2
    DOI 10.1016/j.jclinepi.2016.05.017
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • overfitting
    • epub-replace
    • stratification
  • Bias associated with using the estimated propensity score as a regression covariate

    Type Journal Article
    Author Erinn M. Hade
    Author Bo Lu
    URL http://dx.doi.org/10.1002/sim.5884
    Volume 33
    Issue 1
    Pages 74-87
    Publication Stat Med
    ISSN 1097-0258
    Date 2014-01
    Extra Citation Key: had14bia tex.citeulike-article-id= 12445750 tex.citeulike-attachment-1= had14bia.pdf; /pdf/user/harrelfe/article/12445750/996108/had14bia.pdf; e432263d6788007ac57fbc904f87dbcc4ccad464 tex.citeulike-linkout-0= http://dx.doi.org/10.1002/sim.5884 tex.citeulike-linkout-1= http://view.ncbi.nlm.nih.gov/pubmed/23787715 tex.citeulike-linkout-2= http://www.hubmed.org/display.cgi?uids=23787715 tex.day= 15 tex.pmid= 23787715 tex.posted-at= 2014-11-29 16:49:33 tex.priority= 2
    DOI 10.1002/sim.5884
    Abstract The use of propensity score methods to adjust for selection bias in observational studies has become increasingly popular in public health and medical research. A substantial portion of studies using propensity score adjustment treat the propensity score as a conventional regression predictor. Through a Monte Carlo simulation study, Austin and colleagues. investigated the bias associated with treatment effect estimation when the propensity score is used as a covariate in nonlinear regression models, such as logistic regression and Cox proportional hazards models. We show that the bias exists even in a linear regression model when the estimated propensity score is used and derive the explicit form of the bias. We also conduct an extensive simulation study to compare the performance of such covariate adjustment with propensity score stratification, propensity score matching, inverse probability of treatment weighted method, and nonparametric functional estimation using splines. The simulation scenarios are designed to reflect real data analysis practice. Instead of specifying a known parametric propensity score model, we generate the data by considering various degrees of overlap of the covariate distributions between treated and control groups. Propensity score matching excels when the treated group is contained within a larger control pool, while the model-based adjustment may have an edge when treated and control groups do not have too much overlap. Overall, adjusting for the propensity score through stratification or matching followed by regression or using splines, appears to be a good practical strategy.
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-study
    • propensity-score
    • bias
    • covariable-adjustment
  • The performance of different propensity-score methods for estimating relative risks

    Type Journal Article
    Author Peter C. Austin
    Volume 61
    Pages 537-545
    Publication J Clin Epi
    Date 2008
    Extra Citation Key: aus08per tex.citeulike-article-id= 13265663 tex.posted-at= 2014-07-14 14:10:01 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • review
    • comparison

    Notes:

    • MSE and bias of relative risk;quintile stratification vs. matching;covariate adjustment;"propensity-score matching resulted in estimates with less bias than did stratification on the quintiles of the propensity score, but stratification on the quintiles of the propensity score resulted in estimates with greater precision."

  • Estimation of propensity scores using generalized additive models

    Type Journal Article
    Author Mi-Ja Woo
    Author Jerome P. Reiter
    Author Alan F. Karr
    Volume 27
    Pages 3805-3816
    Publication Stat Med
    Date 2008
    Extra Citation Key: woo08est tex.citeulike-article-id= 13265701 tex.posted-at= 2014-07-14 14:10:02 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • gam
    • observational-study
    • matching
    • logistic-regression
    • causal-inference
    • generalized-additive-model
    • flexible-propensity-score-model
  • For objective causal inference, design trumps analysis

    Type Journal Article
    Author Donald B. Rubin
    Volume 2
    Issue 3
    Pages 808-840
    Publication Ann Appl Stat
    Date 2008
    Extra Citation Key: rub08obj tex.citeulike-article-id= 13265708 tex.posted-at= 2014-07-14 14:10:02 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-studies
    • causal-model
    • noncompliance
    • propensity-scores
    • average-causal-effect
    • causal-effects
    • complier-average-causal-effect
    • instrumental-variable
    • randomized-experiments

    Notes:

    • making observational research more rigorous;observational studies as approximations of randomized experiments;design observational studies to approximate randomized trials;make sure key covariates are measured well

  • A mixed-effects quintile-stratified propensity adjustment for effectiveness analyses of ordered categorical doses

    Type Journal Article
    Author Andrew C. Leon
    Author Donald Hedeker
    Volume 24
    Pages 647-658
    Publication Stat Med
    Date 2005
    Extra Citation Key: leo05mix tex.citeulike-article-id= 13265408 tex.posted-at= 2014-07-14 14:09:56 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-study
    • propensity-score
    • causal-inference
    • mixed-effects-model
    • propensity-analysis
    • propensity-for-treatment-intensity
    • treatment-effectiveness
  • Stratification and weighting via the propensity score in estimation of causal treatment effects: a comparative study

    Type Journal Article
    Author Jared K. Lunceford
    Author Marie Davidian
    Volume 23
    Pages 2937-2960
    Publication Stat Med
    Date 2004
    Extra Citation Key: lun04str tex.citeulike-article-id= 13265389 tex.posted-at= 2014-07-14 14:09:55 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • covariate-balance
    • double-robustness
    • horvitz-thompson-estimator
    • observational-data
    • propensity

    Notes:

    • "Theoretical and empirical results indicate that the popular version of stratification via estimated propensity scores based on within-stratum sample mean differences and a fixed number of strata can lead to biased inference due to residual confounding, and the effect of this bias becomes more serious with increasing sample size. Using more strata can increase the sample size at which the trade-off of bias and variability involved in efficiency takes place, but stratifying on quintiles seems to be the most popular approach in practice, even for substantial sample sizes. Thus, as the trade-off point will be unknown for any specific problem, this approach should be used with caution. An interesting avenue for future research would be to establish guidelines for choosing the number of strata based on theoretical analysis of the rate at which the number of strata should increase with sample size to eliminate bias. A modification of stratification based instead on within-stratum regression estimates of treatment effect can eliminate this bias and achieve dramatic improvements in efficiency, but correct specification of the regression model is essential; otherwise, bias and degradation of performance can result. In this regard, this approach is similar to estimating causal effects via direct regression modelling but is less sensitive to mismodelling. Methods based on weighting are consistent and offer approximately unbiased inference for practical sample sizes. The semiparametric efficient estimator identified by the theory of Robins et al. [13], which incorporates regression modelling as a way to gain efficiency, also yields high precision. Although stratification based on regression and direct modelling can outperform this approach under some conditions, this estimator enjoys the unique 'double robustness' property in that it continues to lead to unbiased estimation of the average causal effect even if the regression models involved do not coincide with the true relationship, affording the analyst broad protection against misspecification not available with these other approaches. The results presented here support routine use of this estimator in practice."; nice derivations of inner workings of propensity score

  • Methods to assess intended effects of drug treatment in observational studies are reviewed

    Type Journal Article
    Author Olaf H. Klungel
    Author Edwin P. Martens
    Author Bruce M. Psaty
    Author Diederik E. Grobbee
    Author Sean D. Sullivan
    Author Bruno H. Stricker
    Author Hubert G. M. Leufkens
    Author A. de Boer
    Volume 57
    Pages 1223-1231
    Publication J Clin Epi
    Date 2004
    Extra Citation Key: Klu04met tex.citeulike-article-id= 13265397 tex.posted-at= 2014-07-14 14:09:55 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • instrumental-variables
    • propensity-score
    • multivariate-confounder-score
    • observational-treatment-comparisons
    • selection-models
  • On the use of discrete choice models for causal inference

    Type Journal Article
    Author Rusty Tchernis
    Author Marcela Horvitz-Lennon
    Author Sharon-Lise T. Normand
    Volume 24
    Pages 2197-2212
    Publication Stat Med
    Date 2005
    Extra Citation Key: tch05use tex.citeulike-article-id= 13265437 tex.posted-at= 2014-07-14 14:09:56 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • causal-inference
    • discrete-choice-models
    • matching-estimator

    Notes:

    • multi-valued treatment propensity model using discrete choice model

  • A comparison of propensity score methods: A case-study estimating the effectiveness of post-AMI statin use

    Type Journal Article
    Author Peter C. Austin
    Author Muhammad M. Mamdani
    Volume 25
    Pages 2084-2106
    Publication Stat Med
    Date 2006
    Extra Citation Key: aus06com tex.citeulike-article-id= 13265481 tex.posted-at= 2014-07-14 14:09:57 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • mi
    • residual-confounding
    • acute-myocardial-infarction
    • pharmacoepidemiology
    • statins

    Notes:

    • propensity adjustment using covariate adjustment;effect on hypothesis tests, relative and absolute effects;residual confounding remained after stratifying by quintiles of propensity;Q-Q plots were more sensitive for showing imbalances;non-collapsibility of odds ratios;matched pairs yielded estimates closer to the null because of this;allowing propensity effect on Y to be quadratic affected the result

  • The performance of different propensity score methods for estimating marginal odds ratios

    Type Journal Article
    Author Peter C. Austin
    Volume 26
    Pages 3078-3094
    Publication Stat Med
    Date 2007
    Extra Citation Key: aus07per tex.citeulike-article-id= 13265602 tex.posted-at= 2014-07-14 14:10:00 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-study
    • propensity-score
    • bias
    • matching
    • simulation
    • matching-can-have-lower-mse-than-covariate-adjustment
  • Combining propensity score matching with additional adjustments for prognostic covariates

    Type Journal Article
    Author Donald B. Rubin
    Author Neal Thomas
    Volume 95
    Pages 573-585
    Publication J Am Stat Assoc
    Date 2000
    Extra Citation Key: rub00com tex.citeulike-article-id= 13265133 tex.posted-at= 2014-07-14 14:09:50 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-study
    • propensity-score
    • causal-inference
    • covariable-adjustment
    • bias-reduction
  • Estimating and using propensity scores with partially missing data

    Type Journal Article
    Author D'Agostino, Jr
    Author Donald B. Rubin
    Volume 95
    Pages 749-759
    Publication J Am Stat Assoc
    Date 2000
    Extra Citation Key: dag00est tex.citeulike-article-id= 13265142 tex.posted-at= 2014-07-14 14:09:50 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • missing-data
    • propensity-score
    • imputation

    Notes:

    • missing data in propensity score;adding extra categories for missing;using indicators of missingness in propensity score to balance on missing data patterns;general location model for likelihood-based analysis of partial data

  • Validating recommendations for coronary angiography following acute myocardial infarction in the elderly: A matched analysis using propensity scores

    Type Journal Article
    Author Sharon-Lise T. Normand
    Author Mary B. Landrum
    Author Edward Guadagnoli
    Author John Z. Ayanian
    Author Thomas J. Ryan
    Author Paul D. Cleary
    Author Barbara J. McNeil
    Volume 54
    Pages 387-398
    Publication J Clin Epi
    Date 2001
    Extra Citation Key: nor01val tex.citeulike-article-id= 13265188 tex.posted-at= 2014-07-14 14:09:51 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • good-example-of-propensity-score-and-matching
    • logistic-model-for-propensity
  • The intensity-score approach to adjusting for confounding

    Type Journal Article
    Author Babette Brumback
    Author Sander Greenland
    Author Mary Redman
    Author Nancy Kiviat
    Author Paula Diehr
    Volume 59
    Pages 274-285
    Publication Biometrics
    Date 2003
    Extra Citation Key: bru03int tex.citeulike-article-id= 13265334 tex.posted-at= 2014-07-14 14:09:54 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • longitudinal-data
    • confounding
    • instrumental-variables
    • propensity-score
    • causal-inference
    • observational-data
    • differential-access-to-care
    • dynamic-propensity-score
    • e-estimation
    • g-estimation
    • marginal-structural-model
    • structural-nested-mean-model
    • time-dependent-confounding
    • time-dependent-propensity-score
  • The role of the propensity score in estimating dose-response functions

    Type Journal Article
    Author G. Imbens
    URL http://konstanza.ingentaselect.com/vl=2884470/cl=22/nw=1/rpsv/ij/oup/00063444/v87n3/s17/p706
    Volume 87
    Pages 706-710
    Publication Biometrika
    Date 2000
    Extra Citation Key: imb00rol tex.citeulike-article-id= 13265382 tex.citeulike-linkout-0= http://konstanza.ingentaselect.com/vl=2884470/cl=22/nw=1/rpsv/ij/oup/00063444/v87n3/s17/p706 tex.posted-at= 2014-07-14 14:09:55 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • causal-inference
    • dose-response-function
    • multivalued-treatment
    • obsevational-study
    • unconfoundedness
  • A controlled trial to improve care for seriously ill hospitalized patients

    Type Journal Article
    Author The SUPPORT Principal Investigators
    URL http://dx.doi.org/10.1001/jama.274.20.1591
    Volume 274
    Pages 1591-1598
    Publication JAMA
    Date 1995
    Extra Citation Key: sup95con tex.citeulike-article-id= 13264925 tex.citeulike-linkout-0= http://dx.doi.org/10.1001/jama.274.20.1591 tex.posted-at= 2014-07-14 14:09:45 tex.priority= 0
    DOI 10.1001/jama.274.20.1591
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • rct
    • propensity-score
    • icu
    • support
  • Does more intensive treatment of acute myocardial infarction in the elderly reduce mortality? Analysis using instrumental variables

    Type Journal Article
    Author Mark McClellan
    Author Barbara J. McNeil
    Author Joseph P. Newhouse
    Volume 272
    Pages 859-866
    Publication JAMA
    Date 1994
    Extra Citation Key: mcc94 tex.citeulike-article-id= 13264588 tex.posted-at= 2014-07-14 14:09:38 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • observational-study
    • propensity-score
    • structural-equations
  • Improving the aggregate performance of psychiatric diagnostic methods when not all subjects receive the standard test

    Type Journal Article
    Author Philip W. Lavori
    Author Martin B. Keller
    Volume 7
    Pages 727-737
    Publication Stat Med
    Date 1988
    Extra Citation Key: lav88imp tex.citeulike-article-id= 13264468 tex.posted-at= 2014-07-14 14:09:36 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • missing-data
    • diagnosis
    • multiple-imputation
    • propensity-score
    • testing
    • horvitz-thompson-estimator
    • verification-bias
    • adjustment
  • A multiple imputation strategy for clinical trials with truncation of patient data

    Type Journal Article
    Author Philip W. Lavori
    Author Ree Dawson
    Author David Shera
    Volume 14
    Pages 1913-1925
    Publication Stat Med
    Date 1995
    Extra Citation Key: lav95mul tex.citeulike-article-id= 13264470 tex.posted-at= 2014-07-14 14:09:36 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • study-design
    • longitudinal-data
    • informative-censoring
    • multiple-imputation
    • propensity-score
    • dropouts
    • completers-analysis
    • last-value-analysis
  • Assessing the sensitivity of regression results to unmeasured confounders in observational studies

    Type Journal Article
    Author D. Y. Lin
    Author B. M. Psaty
    Author R. A. Kronmal
    Volume 54
    Pages 948-963
    Publication Biometrics
    Date 1998
    Extra Citation Key: lin98ass tex.citeulike-article-id= 13264529 tex.posted-at= 2014-07-14 14:09:37 tex.priority= 0 See important letter to the editor by Tyler VanderWeele BCS 64:645-649; 2008
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
    • sensitivity-analysis
    • unmeasured-covariable
  • The continuing evolution of therapy for coronary artery disease: Initial results from the era of coronary angioplasty

    Type Journal Article
    Author D. B. Mark
    Author C. L. Nelson
    Author R. M. Califf
    Author F. E. Harrell
    Author K. L. Lee
    Author R. H. Jones
    Author D. F. Fortin
    Author R. S. Stack
    Author D. D. Glower
    Author L. R. Smith
    Author E. R. DeLong
    Author P. K. Smith
    Author J. G. Reves
    Author J. G. Jollis
    Author J. E. Tcheng
    Author L. H. Muhlbaier
    Author J. E. Lowe
    Author H. R. Phillips
    Author D. B. Pryor
    Volume 89
    Pages 2015-2025
    Publication Circ
    Date 1994
    Extra Citation Key: mar94con tex.citeulike-article-id= 13264577 tex.posted-at= 2014-07-14 14:09:38 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-study
    • cabg
    • propensity
    • adjusted-survival-curves
    • cox-model-applications
    • ptca
    • two-propensity-scores-for-three-treatments
  • Invited commentary: Propensity scores

    Type Journal Article
    Author Marshall M. Joffe
    Author Paul R. Rosenbaum
    Volume 150
    Pages 327-333
    Publication Am J Epi
    Date 1999
    Extra Citation Key: jof99pro tex.citeulike-article-id= 13264363 tex.posted-at= 2014-07-14 14:09:33 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • teaching
    • propensity-score
  • How a court accepted an impossible explanation

    Type Journal Article
    Author Joseph Gastwirth
    Author Abba Krieger
    Author Paul Rosenbaum
    Volume 48
    Pages 313-315
    Publication Am Statistician
    Date 1994
    Extra Citation Key: gas94how tex.citeulike-article-id= 13264122 tex.posted-at= 2014-07-14 14:09:29 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • study-design
    • propensity-score
    • adjustment
    • unmeasured-covariables

    Notes:

    • see follow up articles in am stat 51 no 2 may 1997

  • The application of sample selection models to outcomes research: The case of evaluating the effects of antidepressant therapy on resource utilization

    Type Journal Article
    Author William H. Crown
    Author Robert L. Obenchain
    Author Luella Englehart
    Author Tamra Lair
    Author Don P. Buesching
    Author Thomas Croghan
    Volume 17
    Pages 1943-1958
    Publication Stat Med
    Date 1998
    Extra Citation Key: cro98app tex.citeulike-article-id= 13263952 tex.posted-at= 2014-07-14 14:09:26 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • observational-study
    • propensity-score
    • sample-selection-model
    • treatment-selection-bias
  • Measuring effectiveness: What to expect without a randomized control group

    Type Journal Article
    Author Ralph B. D'Agostino
    Author Heidy Kwan
    Volume 33
    Pages AS95-AS105
    Publication Med Care
    Date 1995
    Extra Citation Key: dag95mea tex.citeulike-article-id= 13263965 tex.posted-at= 2014-07-14 14:09:26 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • teaching-mds
    • observational-study
    • propensity-score
    • bias
    • adjustment
    • retrospective-study
  • Tutorial in Biostatistics: Propensity score methods for bias reduction in the comparison of a treatment to a non-randomized control group

    Type Journal Article
    Author D'Agostino, Jr
    Volume 17
    Pages 2265-2281
    Publication Stat Med
    Date 1998
    Extra Citation Key: dag98pro tex.citeulike-article-id= 13263966 tex.posted-at= 2014-07-14 14:09:26 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • observational-study
    • propensity-score
    • distance-matching
  • Effects of misspecification of the propensity score on estimators of treatment effect

    Type Journal Article
    Author Christiana Drake
    Volume 49
    Pages 1231-1236
    Publication Biometrics
    Date 1993
    Extra Citation Key: dra93eff tex.citeulike-article-id= 13264017 tex.posted-at= 2014-07-14 14:09:27 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
    • bias
    • observation-study
  • The effectiveness of right heart catheterization in the initial care of critically ill patients

    Type Journal Article
    Author Alfred F. Connors
    Author Theodore Speroff
    Author Neal V. Dawson
    Author Charles Thomas
    Author Frank E. Harrell
    Author Douglas Wagner
    Author Norman Desbiens
    Author Lee Goldman
    Author Albert W. Wu
    Author Robert M. Califf
    Author William J. Fulkerson
    Author Humberto Vidaillet
    Author Steven Broste
    Author Paul Bellamy
    Author Joanne Lynn
    Author William A. Knaus
    Author The SUPPORT Investigators
    URL http://www.ncbi.nlm.nih.gov/pubmed/8782638
    Volume 276
    Pages 889-897
    Publication JAMA
    Date 1996
    Extra Citation Key: con96eff tex.citeulike-article-id= 13263914 tex.citeulike-linkout-0= http://www.ncbi.nlm.nih.gov/pubmed/8782638 tex.citeulike-linkout-1= http://dx.doi.org/ tex.posted-at= 2014-07-14 14:09:25 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
  • Asymmetric stratification: An outline for an efficient method for controlling confounding in cohort studies

    Type Journal Article
    Author E. Francis Cook
    Author Lee Goldman
    Volume 127
    Pages 626-639
    Publication Am J Epi
    Date 1988
    Extra Citation Key: coo88asy tex.citeulike-article-id= 13263916 tex.posted-at= 2014-07-14 14:09:25 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • confounding
    • propensity-score
    • cart
    • recursive-partitioning
    • non-randomized-data
  • Dealing with non-ignorable non-response by using an `enthusiasm-to-respond' variable

    Type Journal Article
    Author Andrew J. Copas
    Author Vern T. Farewell
    Volume 161
    Pages 385-396
    Publication J Roy Stat Soc A
    Date 1998
    Extra Citation Key: cop98dea tex.citeulike-article-id= 13263929 tex.posted-at= 2014-07-14 14:09:25 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • bootstrap
    • propensity-score
    • sample-survey
    • non-ignorable-non-response
    • embarrassment-assessment
    • modeling-non-response
    • unit-and-item-non-response
  • The design versus the analysis of observational studies for causal effects: Parallels with the design of randomized studies

    Type Journal Article
    Author Donald B. Rubin
    Volume 26
    Pages 20-36
    Publication Stat Med
    Date 2007
    Extra Citation Key: rub07des tex.citeulike-article-id= 13265546 tex.posted-at= 2014-07-14 14:09:59 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • causal-inference
    • assignment-mechanism
    • blinding-as-much-of-the-analysis-to-outcome-data-as-possible
    • good-review-article
    • objective-analysis-of-observational-studies
    • objective-design
    • tobacco-litigation
  • Causal estimation of time-varying treatment effects in observational studies: Application to depressive disorder

    Type Journal Article
    Author Philip W. Lavori
    Author Ree Dawson
    Author Timothy B. Mueller
    Volume 13
    Pages 1089-1100
    Publication Stat Med
    Date 1994
    Extra Citation Key: lav94cau tex.citeulike-article-id= 13264469 tex.posted-at= 2014-07-14 14:09:36 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • discrete-survival-model
    • tdc
    • dynamic-treatment
    • repeated-logistic-model
  • Two-stage least squares estimation of average causal effects in models with variable treatment intensity

    Type Journal Article
    Author Joshua D. Angrist
    Author Guido W. Imbens
    Volume 90
    Pages 431-442
    Publication J Am Stat Assoc
    Date 1995
    Extra Citation Key: ang95two tex.citeulike-article-id= 13263703 tex.posted-at= 2014-07-14 14:09:21 tex.priority= 0
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • instrumental-variables
    • propensity-score
    • causal-inference
    • two-stage-models
  • On regression adjustment for the propensity score

    Type Journal Article
    Author S. Vansteelandt
    Author R. M. Daniel
    URL http://dx.doi.org/10.1002/sim.6207
    Volume 33
    Issue 23
    Pages 4053-4072
    Publication Stat Med
    ISSN 02776715
    Date 2014-10
    Extra Citation Key: van14reg tex.citeulike-article-id= 13340175 tex.citeulike-attachment-1= van14reg.pdf; /pdf/user/harrelfe/article/13340175/982683/van14reg.pdf; 7b2d0837c91c0d47441b5588ee35f8a735dd2f7b tex.citeulike-linkout-0= http://dx.doi.org/10.1002/sim.6207 tex.day= 15 tex.posted-at= 2014-08-28 19:21:49 tex.priority= 4
    DOI 10.1002/sim.6207
    Abstract Propensity scores are widely adopted in observational research because they enable adjustment for high-dimensional confounders without requiring models for their association with the outcome of interest. The results of statistical analyses based on stratification, matching or inverse weighting by the propensity score are therefore less susceptible to model extrapolation than those based solely on outcome regression models. This is attractive because extrapolation in outcome regression models may be alarming, yet difficult to diagnose, when the exposed and unexposed individuals have very different covariate distributions. Standard regression adjustment for the propensity score forms an alternative to the aforementioned propensity score methods, but the benefits of this are less clear because it still involves modelling the outcome in addition to the propensity score. In this article, we develop novel insights into the properties of this adjustment method. We demonstrate that standard tests of the null hypothesis of no exposure effect (based on robust variance estimators), as well as particular standardised effects obtained from such adjusted regression models, are robust against misspecification of the outcome model when a propensity score model is correctly specified; they are thus not vulnerable to the aforementioned problem of extrapolation. We moreover propose efficient estimators for these standardised effects, which retain a useful causal interpretation even when the propensity score model is misspecified, provided the outcome regression model is correctly specified.
    Date Added 7/7/2018, 1:38:33 PM
    Modified 11/8/2019, 8:01:59 AM

    Tags:

    • propensity-score
    • covariate-adjustment

    Notes:

    • From first author in ASA Connections discussion:I share your concerns and also tend to favour regression adjustment for the propensity score for the following additional reasons:- it adjusts for residual confounding due to imperfect matching;- it makes more efficient use of the information in the data;- adjustment for both the propensity score and covariates can result in estimators with a double robustness property: they are valid if either the propensity score is correct or the covariates in the outcome model are correctly modelled.- matching is often preferred for simplicity, but I tend to believe that regression adjustment for the propensity score is much simpler because one loses the simplicity of matching whenever one wishes to adjust for residual confounding due to imperfect matching or wishes to obtain valid standard errors.

      Note that, like matching methods, regression adjustment for the propensity score also prevents the dangers of model extrapolation in settings where the treated and untreated are very different in their observed covariate data, in the sense that- subjects with covariate values at which there are nearly only treated or non-treated individuals are down-weighted, as they contribute little or no information about treatment effect;- valid estimators of treatment effect can be obtained when the propensity score model is correct, even when the association between outcome and propensity score is misspecified. This follows from the aforementioned double robustness property.

  • Avoiding pitfalls when combining multiple imputation and propensity scores

    Type Journal Article
    Author Emily Granger
    Author Jamie C. Sergeant
    Author Mark Lunt
    URL https://onlinelibrary.wiley.com/doi/abs/10.1002/sim.8355
    Rights © 2019 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.
    Volume 38
    Issue 26
    Pages 5120-5132
    Publication Statistics in Medicine
    ISSN 1097-0258
    Date 2019
    DOI 10.1002/sim.8355
    Accessed 10/21/2019, 8:31:09 AM
    Library Catalog Wiley Online Library
    Language en
    Abstract Overcoming bias due to confounding and missing data is challenging when analyzing observational data. Propensity scores are commonly used to account for the first problem and multiple imputation for the latter. Unfortunately, it is not known how best to proceed when both techniques are required. We investigate whether two different approaches to combining propensity scores and multiple imputation (Across and Within) lead to differences in the accuracy or precision of exposure effect estimates. Both approaches start by imputing missing values multiple times. Propensity scores are then estimated for each resulting dataset. Using the Across approach, the mean propensity score across imputations for each subject is used in a single subsequent analysis. Alternatively, the Within approach uses propensity scores individually to obtain exposure effect estimates in each imputation, which are combined to produce an overall estimate. These approaches were compared in a series of Monte Carlo simulations and applied to data from the British Society for Rheumatology Biologics Register. Results indicated that the Within approach produced unbiased estimates with appropriate confidence intervals, whereas the Across approach produced biased results and unrealistic confidence intervals. Researchers are encouraged to implement the Within approach when conducting propensity score analyses with incomplete data.
    Date Added 10/21/2019, 8:31:09 AM
    Modified 10/21/2019, 8:31:42 AM

    Tags:

    • imputatation
    • propensity
    • missing
  • Should a propensity score model be super? The utility of ensemble procedures for causal adjustment

    Type Journal Article
    Author Shomoita Alam
    Author Erica E. M. Moodie
    Author David A. Stephens
    URL https://onlinelibrary.wiley.com/doi/abs/10.1002/sim.8075
    Rights © 2018 John Wiley & Sons, Ltd.
    Volume 0
    Issue 0
    Publication Statistics in Medicine
    ISSN 1097-0258
    Date 2018
    DOI 10.1002/sim.8075
    Accessed 12/31/2018, 9:26:20 AM
    Library Catalog Wiley Online Library
    Language en
    Abstract In investigations of the effect of treatment on outcome, the propensity score is a tool to eliminate imbalance in the distribution of confounding variables between treatment groups. Recent work has suggested that Super Learner, an ensemble method, outperforms logistic regression in nonlinear settings; however, experience with real-data analyses tends to show overfitting of the propensity score model using this approach. We investigated a wide range of simulated settings of varying complexities including simulations based on real data to compare the performances of logistic regression, generalized boosted models, and Super Learner in providing balance and for estimating the average treatment effect via propensity score regression, propensity score matching, and inverse probability of treatment weighting. We found that Super Learner and logistic regression are comparable in terms of covariate balance, bias, and mean squared error (MSE); however, Super Learner is computationally very expensive thus leaving no clear advantage to the more complex approach. Propensity scores estimated by generalized boosted models were inferior to the other two estimation approaches. We also found that propensity score regression adjustment was superior to either matching or inverse weighting when the form of the dependence on the treatment on the outcome is correctly specified.
    Short Title Should a propensity score model be super?
    Date Added 12/31/2018, 9:26:20 AM
    Modified 12/31/2018, 9:27:50 AM

    Tags:

    • covariate-adjustment
    • propensity
    • covariable-adjustment
    • machine-learning
  • Matched or unmatched analyses with propensity-score–matched data?

    Type Journal Article
    Author Fei Wan
    URL https://onlinelibrary.wiley.com/doi/abs/10.1002/sim.7976
    Rights © 2018 John Wiley & Sons, Ltd.
    Volume 38
    Issue 2
    Pages 289-300
    Publication Statistics in Medicine
    ISSN 1097-0258
    Date 2019
    DOI 10.1002/sim.7976
    Accessed 12/16/2018, 8:07:57 PM
    Library Catalog Wiley Online Library
    Language en
    Abstract Propensity-score matching has been used widely in observational studies to balance confounders across treatment groups. However, whether matched-pairs analyses should be used as a primary approach is still in debate. We compared the statistical power and type 1 error rate for four commonly used methods of analyzing propensity-score–matched samples with continuous outcomes: (1) an unadjusted mixed-effects model, (2) an unadjusted generalized estimating method, (3) simple linear regression, and (4) multiple linear regression. Multiple linear regression had the highest statistical power among the four competing methods. We also found that the degree of intraclass correlation within matched pairs depends on the dissimilarity between the coefficient vectors of confounders in the outcome and treatment models. Multiple linear regression is superior to the unadjusted matched-pairs analyses for propensity-score–matched data.
    Date Added 12/16/2018, 8:07:57 PM
    Modified 12/16/2018, 8:08:46 PM

    Tags:

    • matching
    • covariate-adjustment
    • propensity