Date
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Article Title
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Presenter
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Presenter & Teaching Points
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9/18/2024 |
Against quantiles: categorization of continuous
variables in epidemiologic research, and its Discontents.
And
Cubic splines to model relationships between continuous variables and outcomes: a guide for clinicians. |
Maggie Westerland, MA
Statistical Programmer and Clinical Data Manager, Rheumatology
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Teaching Points
- If an investigator is interested in employing this statistical approach, they may talk to the assigned statistician for the appropriate way to do this
- Splines capture non-linearity between variables, something that is lost when data is binned/categorized
- Using restricted cubic splines is a way to keep continuous variables , continuous. They work by allowing for a more true representation of the relationship between the continuous predictor and the outcome .
- Most cases, it is better to keep continuous variables continuous , there are some exceptions however
- Request a consult: Information or email mcrc@bu.edu
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10/16/2024 |
Regression without regrets: Initial Data analysis is a prerequisite for Multivariable regression. |
Michael LaValley, PhD
Professor, Department of Biostatistics
BU School of Public Health |
Teaching Points
- Findings from IDA can provide refinements to the analysis plan and guide the later regression analyses.
- IDA should focus on a) missing data, b) univariate distributions, and c) multivariate associations among the predictors.
- IDA is not exploratory data analysis and should not probe the associations between predictors and the outcome.
- Initial Data Analysis (IDA) is intended to provide reliable information about the data before starting regression analyses to address the primary research question.
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11/19/2024 |
Canceled for ACR Conference |
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12/4/2024 |
Misconceptions About the Direction of Bias From Nondifferential Misclassification. |
Jean Liew, MD
Assistant Professor, Rheumatology |
Teaching Points
Measurement error can also be called information bias
Misclassification refers to binary and categorical variables
- Misclassification can be differential vs nondifferential. Ex of differential misclassification: when disease status changes how people report exposure (recall bias)
Misclassification can be dependent vs independent.
- We learn that nondifferential misclassification biases estimates towards the null.
It’s cited in Discussion (limitation) sections of papers all the time.
But it’s not always true.
- Overall we expect to have nondifferential misclassification
Actual/observed estimate from a single study may not be biased towards the null, due to chance
It’s worse with smaller sample sizes
- Misclassifying some levels of a categorical exposure can lead to bias away from the null
Collapsing nondifferentially misclassified exposure categories can lead to unpredictable bias
- Dependent nondifferential misclassification of the exposure or outcome can lead to unpredictable bias, even with small amounts of misclassification
Ex: when the same instrument is used to measure both exposure & outcome & people might tend to respond the same way
- Nondifferential outcome misclassification: if perfect Sp but low Se (like with a fracture outcome), expect the RR to be unbiased
There is a calculation for the bias expected for the RD (related to the Se)
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1/8/2015 |
Using Big Data to Emulate a Target Trial When a Randomized Trial Is Not Available |
Brooke McGinley
Doctoral Student, Department of Biostatistics |
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2/5/2025 |
“Limitations of Minimal Clinically Important Difference Estimates and Potential Alternatives”
Article:
Response to Riddle and Dumenci on “Prospective Back Pain Trajectories or Retrospective Recall-Which Tells Us Most About the Patient?”
|
Gillian Fennell PhD
Postdoctoral Associate NRSA, Rheumatology, T32 Scholar
Dan Riddle PhD, author as discussant |
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3/5/2025 |
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Sarah Tilley, MS
Statistical Programmer, Rheumatology
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4/2/2025 |
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Hung Vo, MD
Clinical Instructor Rheumatology , T32 Scholar |
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5/7/2025 |
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Michelle Yau, PhD, MPH
Visiting researcher |
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6/4/2025 |
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Maggie Westerland
Statistical Programmer and Clinical Data Manager, Rheumatology
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