Department of Medicine

Quantitative Sciences Unit

Research Methods Seminars

Directions

To get to 1070 Arastradero:
Driving: enter the driveway and take the first left into the parking lot and park.  Enter through the front door - you will be in the lobby.  Take the door on the right and follow it toward the back of the building.  Room 109 will be on your left before you reach the glass door leading outside.
Shuttle: 1070 Arastradero is served by the Marguerite Shuttle, which picks up at the medical center on Pasteur Drive. 

The Quantitative Sciences Unit (QSU) is hosting a forum to discuss research methods in medicine held on the first Tuesday of every month.

The Research Methods Seminar is an interactive and informal journal club-type format where topical papers in medical research, particularly relevant to faculty in the Department of Medicine, are discussed with an emphasis on the methods and/or study design.

 

QSU Research Methods Seminar
Location: 1070 Arastradero Road # 109
Time: 4-5pm first Tuesday of the month (unless otherwise noted)
 Refreshments served
Free parking

Upcoming Seminars

Tuesday, May 7, 2013

Aya Mitani, MPH
Biostatistician, Quantitative Sciences Unit

Multiple Imputation in Practice -- Approaches for handling categorical and interaction variables

Missing data is a pervasive problem in medical and epidemiological research. Multiple imputation (MI), a simulation-based method, is one reasonable approach for handling missing data. Recently, mainstream statistical packages such as SAS, STATA and R have incorporated MI procedures allowing easy access to its use. While in theory MI yields valid results when data are missing at random (MAR), in practice the story is more nuanced. Much of the burden remains on the user for appropriate application in order for validity to hold. For example, MI is not completely straightforward in the presence of categorical variables, derived variables or interaction terms. Further, different software packages not only rely on different methods for imputation but also make different options available for handling these subtleties. Such variations impact results. We discuss common issues that arise in multiple imputation and present practical guidelines based on previous research and available software on how best to employ MI in these scenarios.

Optional Reading:

  • van Buuren, S. Multiple imputation of discrete and continuous data by fully conditional specification. Statistical Methods in Medical Research, 16(3): 219-242, 2007
  • von Hippel, PT. How to impute interactions, squares and other transformed variables. Sociological Methodology, 39: 265-291, 2009

We welcome your suggestions for the seminar series and are happy to answer any questions you may have - please contact Linda Enomoto or Jessica Kubo.

We look forward to seeing you at our next seminar!


Past Seminars
April 2013 Kristin Sainani
Writing about Biostatistics
March 2013 Iryna V. Lobach
Analysis of Gene-Environment Interactions with Measurement Errors in Environmental Exposures
February 2013 Ying Lu
Statistical Designs for Phase I Cancer Clinical Trials
December 2012 Sergio Bacallado
An Introduction to Bayesian Analysis Using Case Studies in Medical Research
November 2012 Kristin Sainani
Introduction to Propensity Scores
October 2012 John Ioannidis
Genetic Prediction Models: Practice, Metrics and a Discovery Extension
May 2012 Ben Goldstein
Predicting Acute Sudden Cardiac Death using Electronic Health Records
April 2012 Sepideh Modrek
An Application of Instrumental Variables: Maternal Education as a Driver for Eliminating Female Circumcision
March 2012 Hui Wang
Applications of Targeted MLE Based Variable Importance Measurement in Dimension Reduction with Gene Expression Data
February 2012 Mike Baiocchi
Estimating the Effectiveness of Intensity of Care on Rates of Death for Premature Infants
January 2012 Raúl Aguilar
Things You Can Do When You Have Missing Covariates
December 2011 David Shilane
Comparative Effectiveness Research in Cardiology with Messy Data
November 2011 Ben Goldstein
Prediction in Medical Studies: What, Why & How
October 2011 Jane Paik
Using Regression Models to Analyze Randomized Trials: Robustness of Survival Models to Misspecification
September 2011 David Rehkopf
Applying Machine Learning Algorithm to Answer Questions from Observational Data: Essential Complement or Dangerous Tool?
June 2011 Susan Gruber
Targeted Maximum Likelihood Estimation for Causal Inference
May 2011 Gunnar Carlsson
Topological Data Analysis for Biology
April 2011 Maria E Montez-Rath
Methods for Handling Survey Data
March 2011 Mark Cullen, Manisha Desai, Jessica Kubo
Modeling the Hazard of Injury as a Function of Experience Among Hourly Aluminum Manufacturing Workers
February 2011 Jose Montoya
Could a Recently Found Virus, XMRV, Cause Chronic Fatigue Syndrome?
January 2011 Manisha Desai
An Introduction to Missing Data and Imputation Methods
December 2010 Wolfgang Winkelmayer
Propensity Scores
November 2010 Jay Bhattacharya
Does Swan-Ganz Catheterization Increase Mortality in the ICU? An Instrumental Variables Bounding Approach
October 2010 Tim Assimes
Epidemiological Issues in Contemporary Human Genetic Studies
September 2010 Doug Owens
Where Angels Dare not Tread: Development of a Guideline for Screening Mammography in 40 to 49 year Old Women

Additional Information:

Welcome to Quantatitive Sciences
Quantative Sciences Overview

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