Linked Questions
15 questions linked to/from Is there a mathematical proof for change being correlated with baseline value
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What are the worst (commonly adopted) ideas/principles in statistics?
In my statistical teaching, I encounter some stubborn ideas/principles relating to statistics that have become popularised, yet seem to me to be misleading, or in some cases utterly without merit. I ...
9
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Difference between Repeated measures ANOVA, ANCOVA and Linear mixed effects model
What is the best way to analyze these data:
Subjects are divided in two "Group" (Treatment A and B).
"Weight" is recorded before and 3 months after treatment.
Outcome variable: ...
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1
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Controlling for baseline in pre-post between design: using $\Delta(T_2-T_1)$ or controlling for T1 in the regression model (or both)? [duplicate]
I have a mixed between-within design, with three groups and Pre (T1) and Post (T2) measurements. I'm hesitating on the right statistical analyses to do, but I would like to compare each group to the ...
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How to properly perform "change from baseline" (pre-post) analysis adjusting for pre using lme4 in R?
Let's assume I have the following data set, consisting of pre (t1) and post (t2) measurements. I want to check, if there is a significant effect over time (t1, t2).
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How should interactions be modeled in mixed-models?
It is confusing because I get so many different sources claiming different ideas. I am going to try to make it simple.
Several individuals organised in 3 groups. We measure multiple variables at two ...
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1
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Analysing change scores via linear mixed effects model with baseline adjustment?
I am still trying to find a model for a large dataset, approximately 1-5 measurements per patient (over time), one is the baseline value at t=0. The researcher is interested in the change over time ...
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Different ways to include pre-test performance as a covariate in a linear mixed-effect regression. Which is correct?
I have a pre-post experimental design, where I have measured participants' performance in three courses (tasks; A, B, C) at both pre and post-test. The study is a learning experiment. 60 elite alpine ...
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2
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1
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Should I include covariates with a non-linear relationship to the dependent variable in linear regression?
In my linear regression model, baseline BMI is a significant predictor of BMI change following a weight loss intervention and including it improves fit (e.g. AIC). But it is strongly associated with ...
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1
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Change Score or Regressor Variable Method - Should I regress $Y_1$ over $X$ and $Y_0$ or $(Y_1-Y_0)$ over $X$
I have data about investment preferences 1 year before the Covid and during the Covid lockdown.
Some changes appear using simple T-Test. I want to be able to assess if these changes are particularly ...
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Keeping baseline as predictor with change score as outcome in this peculiar scenario
It is generally recommended that baseline should not be kept as predictor if change score ...
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Subgroup analysis: post hoc test interpretation
I am modeling treatment effect in a hypothetical case where only a subset of the sample has disease-related impairment on the outcome of interest. I only expect treatment effects in this subset, but ...
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How is it possible, that statisticians have OPPOSITE view on the analysis of change from baseline adjusted for baseline?
I always thought, that mathematics, thus statistics, are both strict sciences. So, two mathematicians cannot speak about the same topic and have contrary views on it.
In the pharmaceutical industry, ...
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2
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1
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Analysing change data between 3 groups
I have used a mixed-model ANOVA to examine changes in weight following an 8-week intervention in 3 groups (Control, Diet A, & Diet B).
The ANOVA identified significant within group differences ...
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1
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Is it reasonable/possible to use pre-scores as predictors of change?
In change analyses (of any variable, from pre to post) we usually controll for the pre-score, as it may affect the rate of change. However, what if I am especially interested in the effect of the pre ...
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Is it appropriate to use GLMM for the dataset I have
I am interested in determining the influence of biotic (initial height) and abiotic (light, canopy, soil moisture content, soil nutrients, rainfall, and temperature) factors in the absolute height-...
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