Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [case-control-study]

An observational study in which two existing groups differing in outcome are identified and compared on the basis of some supposed causal attribute.

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Does down-sampling change logistic regression coefficients?

If I have a dataset with a very rare positive class, and I down-sample the negative class, then perform a logistic regression, do I need to adjust the regression coefficients to reflect the fact that I changed the prevalence of the positive…
Zach
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Estimating logistic regression coefficients in a case-control design when the outcome variable is not case/control status

Consider sampling data from a population of size $N$ in the following way: For $k=1, ..., N$ Observe individual $k$'s "disease" status If they have the disease, include them in the sample with probability $p_{k1}$ If they do not have the disease,…
Macro
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Optimal case/control ratio in a case-control study

What is the optimal case/control ratio in a case-control study? Why do most textbooks or monographs suggest that it is more than 1? Can it be less than 1 (what are the drawbacks?)? Thank you.
KuJ
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What is the difference between a Frequentist approach with meta-analysis and a Bayesian approach?

Say I am performing an analysis looking at a particular health measure. I am interested in the difference in that measure between patients and controls and whether or not the difference is different from 0. There have been studies in the past…
derrek
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How to make the rare events corrections described in King and Zeng (2001)?

I have a dataset with a binary (survival) response variable and 3 explanatory variables (A = 3 levels, B = 3 levels, C = 6 levels). In this dataset, the data is well balanced, with 100 individuals per ABC category. I already studied the effect of…
Aurelie
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How to design experiment and holdout for two types of treatment at the same time

Let's say there are two types of treatment, namely treatment A and treatment B. A subject can be in one of these categories: get treatment A and then treatment B. get treatment B and then treatment A. get only treatment A. get only treatment B. get…
Patrick the Cat
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Why is relative risk not valid in case control studies?

I'm getting my information from: http://sphweb.bumc.bu.edu/otlt/mph-modules/ep/ep713_analyticoverview/EP713_AnalyticOverview5.html It says that in a case-control study, you can not compute the probability of disease in each exposure group because…
Plumpie
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What does "case-control" and "cross-sectional" mean in the context of logistic modeling?

While studying logistic modeling, I read the following statement The fact that only odds ratios, not individual risks, can be estimated from logistic modeling in case-control or cross-sectional studies is not surprising. I do not know what do…
user3125
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Case-control study and Logistic regression

Suppose we have case-control data, where cases have some disease ($Y$) and controls don't and we are interested in the association of some other variable(s) ($X$). I know that in this scenario we cannot use the disease as the response variable…
bdeonovic
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How to interpret odds ratio?

Suppose we have a baseline exposure group and 2 other exposure groups for a case control study. Suppose the odds ratio for the first exposure is $1.5$ and the odds ratio for the second exposure is $1.8$. Does this mean that cases are $1.5$ times as…
guestguy
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Can I validly expand the odds ratio analogously to the relationship between relative risk & the incidence rate ratio?

I am involved in a nested Case-Control study that involves cohorts of cases and controls entering a program, with the outcome of failure by six months. Cases and controls are individually matched on month / year of entry. I have a lot (>10,000) of…
David Cowan
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Review of case control matching algorithms?

Can you suggest a good review of case control matching algorithms? Algorithms that can be used to set up the matched pairs of one case and one control, or matched blocks of a case and multiple controls.(Preferably a paper, book chapter or website…
GaBorgulya
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During oversampling of rare events, why are the beta coefficients of the independent variables not affected, but only the intercept?

I have followed the King and Zeng paper and understand the consistency of the prior correction after oversampling in logistic regression. But I am trying to understand why the beta coefficients of the independent variables are not affected by the…
Kingstat
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Follow-up updates in case-cohort designs

In a case cohort, you randomly sub-sample some feasible number of the cohort (say 20%) and then afterwards add all of the cases that were not part of the sub-sampling. So while a case-cohort is easy to set-up in can be tough to analyse, but there…
user4673
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Probabilities in case-controlled studies

I have a nested-case control study that I have been using for analysis. At the end of my work I have deduced a set of variables that I use later to to classify new cases. One example of a simple classifier I am using is a naive Bayes, which will…
user4673
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