Questions tagged [relative-risk]
The relative risk (also called 'risk ratio') is the quotient of the probabilities of an event under two conditions (ie, p1/p2). The RR has a possible range of [0, +infinity). It is a common measure of effect size in biomedical research.
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Relative risk but using the full population and a subset thereof
Consider the probability $p$ of an event in the full population, and the probability $p_0$ of the same event for a subset of the population. In other words, $p_0$ is a conditional probability (...
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Bootstrap produces inf confidence interval
I am using bootstrapping to calculate confidence intervals for a risk ratio. In some of the bootstrapped samples, there are no observations of one of the outcomes, leading to the risk ratio being ...
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Use of $p_1/(p_1+p_2)$ to compare two probabilities $p_1$, $p_2$?
Let's say we want to compare two probabilities $p_1$ and $p_2$, not necessarily referred to the same population. For example, $p_1$ may be the probability of getting a certain disease conditioned on ...
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How to use R glm() to estimate risk ratios and ratio of risk ratios with confidence intervals
Given these data, reflecting individual data on 206 subjects, two treatment groups ("uc" and "texting") and race ("nonblack" and "black").
My goal is a ...
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Score for over/under representations of a variable in sub-group
I have a corpus of book publications split into different clusters. I have information about the nationality of the authors (variable A) and the nationality of the publishing company (variable B).
In ...
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distributed lag non-linear models, DLNM r package
I am new to statistics and a beginner in DLNM. I am trying to understand the different functions of DLNM.
In the 'crosspred' of DLNM, the exponentiated regression coefficient from the Poisson models, ...
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Calculate Risk Ratio with CI in R from Odds ratios
I have performed a multiple logistic regression because I wanted to see the association between Death and Cardiovascular disease. I adjusted using age, sex, risk factors.
The result came in ODDS RATIO ...
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Relative Risk and Odd ratio for N x N x N table
I am trying to calculate RR for case where I have N x N x N table. First N is City (20 cities) second N is Age group (5 groups) and third one is Industry (4 ...
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How to interpret adjusted vs unadjusted RR?
I've run some regressions, and I'm having a hard time discerning the meaning of my results.
My output of interest is diabetes. My variables are low income status, being obese, and hypertension.
So my ...
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How can I estimate the Relative Risk using quasi-Poisson regression?
In studies that relate pollution to hospitalizations for certain diseases, the authors usually present the results in the form of relative risk for a 95% confidence interval.
If I have the regression ...
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Questionable statistic - conflict between chi square stat / relative risk reported
A recent high profile paper claimed to have found signals of harm from a particular intervention, which to avoid bias I'll refrain from identifying. The methodology is unusual and result controversial ...
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Log-binomial or IPTW for Imbalanced sample
I have a binary outcome of depression and exposure variable of a 4-level categorical variable of diet, diet1 group has 300 participants, diet2 has 40, diet3 has 30 and diet4 has 450. For this ...
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Is it possible to calculate the SD of observations for a RR based solely on the confidence interval and mean?
Set up:
I have a epidemiological study with a dose-response curve with a series of relative risk estimates (risk ratio of mortality risk exposed compared to mortality risk unexposed) along a curve. ...
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Why Do We Need Relative Risk?
I am an MBA student that is taking courses in statistics. In our classes, we are learning about Odd's Ratios and Relative Risk.
Our Prof outlined the following examples:
Example 1: Suppose we take a ...
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How to convert continuous relative risks per exposure unit?
If a study for example concludes that the relative risk of a cardiovascular event is 1.04 per 10 µg/m³ increase in NO2, how can I calculate the relative risk for an air pollution concentration of for ...
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error propagation to get confidence interval for relative risk when only standard errors for numerator and denominator are known?
How do I calculate a confidence interval around a relative risk (risk ratio) when all I have are predicted values from a regression model and their standard errors?
I developed a generalised additive ...
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how to get relative risk from a GAM with a distributed lag model
I would like to obtain a relative risk/ risk ratio from a GAM
with a distributed lag model. I have a GAM (implemented in mgcv in R) predicting daily deaths from time series data consisting of daily ...
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Assumption of Poisson regression with robust standard errors
I am applying a Poisson regression with robust standard errors to model a binary response variables. I was wondering what are the assumptions underlying this type of regression?
I understand that the ...
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Approximate p-values for Relative Risk Reduction
I am working on a problem in which I compare the probability of infection within a region before treatment, and again after 5 years of Mass Drug Administration (MDA). Below describes the sampling ...
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Calculate a permutation-based p-value for a risk ratio
Summary
How do you calculate a two-sided p-value for a risk ratio/relative risk (obtained from a GEE logistic regression via predicting risks with and without a treatment) based on a permutation test, ...
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In a survival meta-analysis shouldn't you use HR instead of RR?
I found this interesting survival meta-analysis: https://pubmed.ncbi.nlm.nih.gov/23216926/
Why do they compare OS between the different studies using RR and not HR?
Indeed the authors of this paper ...
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Asymptotic variance of relative risk
I'm interested in the asymptotic variance of relative risk (without sample size). I know that in an application, the variance is
$$
\frac{1-p_1}{n_1p_1} + \frac{1-p_0}{n_0p_0}
$$
When removing $n$ ...
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Hazard ratio and relative risk (or odds ratio) in case of very few event/censoring times
As far as I understand relative risks and hazard ratios are very similar concepts (although this paper seems to disagree). The advantage of hazard ratios is the inclusion of temporal information. I ...
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Kernel Density: How do the terms 'global' and 'pilot' translate?
I nearly most of the articles on kernel smoothing or concepts that use kernel density estimations, authors speak of 'pilot' and 'global'.
https://link.springer.com/article/10.1023/A:1008925425102
&...
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Is there a good graphical representation for the sampling distribution of relative risk?
For pedagogical reasons, I am interested in communicating graphically the sampling distribution of relative risks (histogram and CDF plot), specifically in the context of a matched-pair study design:
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Relative risk trees (recursive partitioning for survival data) - node outcome
I am fitting relative risk trees for right-censored data (LeBlanc M. & Crowley J. Relative risk trees for censored survival data. Biometrics, pages 411–425, 1992) with rpart, but I have some ...
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convert the ATE Average Treatment Effect from a doubly robust model into Risk Ratio
How would one convert the ATE Average Treatment Effect from a doubly robust model into Risk Ratio? Can this be done directly without having to convert to odds ratio first. If so, how is this done. Can ...
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Power analysis for relative risk equivalent to power analysis for difference between two proportions?
I need to make a power analysis calculation to estimate the minimum sample size for a relative risk statistic (ratio of two proportions) for unmatched data - two independent samples.
Can I use the ...
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Interpretation of the E-value for non-epidemiologists
A recent method for sensitivity analysis is the E-value (VanderWeele and Ping, 2017). Yet, I'm still struggling with the interpretation of such a value.
Coming from outside of epidemiology, where risk ...
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Metanalysis in R risk ratio compared to log risk ratio?
I have conducted a meta-analysis with the risk ratios and standard errors that have been provided to me. I cannot use the raw data.
I was wondering if I should use the log of the risk ratio and the ...
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Paremater estimation in relative risk regression
While reading a study on leukaemia risk from ionizing radition, I am trying to understand how the model parameters are estimated.
The outcome variable $y$ in this study is binary (leaukaemia or not), ...
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Combined relative risk in meta study
I am looking at a meta study, and I've never done one (or looked at it much) before. From what I've learned about it so far, the way you calculate the compounded effect is by first calculating this $\...
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Is combining Odds Ratios with Relative Risk in a Meta-Analysis Possible?
Can I combine ORs and RRs using generic inverse variance if the the event rare?
There appears to be simple methods for converting ORs into RRs so would I do the conversion first and then apply the ...
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Comparison of predictors in multinomial logit
I have been reading up on ways to understand variable importance in multinomial logistic so as to compare the predictors. My goal is to understand whether predictor A or B is playing a more ...
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Relative Risk, confidence interval and sample size relationship
I'm following this example (see below for the source):
Breast Cancer
No Breast Cancer
Total
DDT exposed
360
13636
13996
Unexposed
1079
76313
77392
...
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odds ratio to relative risk equation, how is it derived?
How is this equation derived? thanks
RR=OR/((1−Pref)+(Pref∗OR))
RR = risk ratio; OR = odds ratio;
Pref = Prevalence of the outcome in the reference group
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Is this how to convert odds ratio intervals to risk ratios
I have a binary logistic regression with just one binary factor predictor. I would like to report the 'risk ratio' (probability ratio) with a confidence interval. I'm using R 4.0.4 for statistical ...
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Am I misunderstanding Zou's method for computing relative risk for binary outcomes using Poisson regression?
It seems that relative risk estimation using Poisson regression is a popular approach in epidemiology, with a couple of papers I have recently looked at (for example [3] and many others like it) ...
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Converting Hazard Rate Ratio and Relative Risk to standardized effect size (eg Cohen's d)
We are 2 psychology students writing a systematic review. We need to convert the effect sizes from the different studies to Cohen's d (or another standardized effect size).
Can anyone help converting ...
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Estimating risk ratio instead of odds ratio in mixed effect logistic regression in `R`
glmer is used to estimate effects on the logit scale of y when the data are clustered. In the following model
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How to tackle increasing survival probability?
I want to model probability of an event, which is typically modelled by survival methods. However, the predicted survival function is always non-increasing. My case is however opposite: The ...
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Confidence interval for relative risk with uncertain incidences
The usual suggestion for computing a confidence interval for a relative risk estimate is to start from the variance:
$$
\text{CI}_R = R \pm z \cdot \exp \sqrt{\sigma^2_{\log R}}
$$
where $R$ is the ...
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Can the Fisher exact test be used to get a confidence interval for the efficiency of a vaccine (risk ratio or relative risk)?
Consider the Pfizer vaccine for COVID-19. The data from the phase 3 trials shows that they had 21720 people in the vaccinated group and 21728 people in the control group:
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Sum of $n$ relative risk ratios and Poisson regression
Consider $n$ joint PMF defined by two Bernoulli r.v. $X_i$ and $Y$. The probability $P(X_i, Y)$ is estimated as:
$$\begin{array}{c|cc}
& Y = 1 & Y = 0 \\
\hline
X_i = 1 & \frac{a_i}{a_i + ...
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Confidence interval of Relative Change using Delta method
I have the following equation for relative change (RC):
RC = (P1 - P2)/P2 * 100
Here, P1 and P2 are both ratios. For example, P1 = A1/n1 and P2 = A2/n2, where n1 and n2 are the sample sizes of both P1 ...
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interpretation of odds ratio for continuous predictor
I'm examining the influence of new venture product maturity on different type of investments (none, angel, crowdfunding, and series investments). I have multiple measures for each firm.
The variable ...
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Why is the log of relative risk ratio closer to normal distribution?
See here: https://en.wikipedia.org/wiki/Relative_risk#Inference
The sampling distribution of the $\log(RR)$is closer to normal than the distribution of RR, with standard error
$$SE(\log(RR)) = \sqrt{\...
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Which statistical model is being used in the Pfizer study design for vaccine efficacy?
I know there's a similar question here:
How to calculate 95% CI of vaccine with 90% efficacy?
but it doesn't have an answer, at the moment. Also, my question is different: the other question asks how ...
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How exactly is the "effectiveness" in the Moderna and Pfizer vaccine trials estimated?
As in the title. Is this "a risk ratio"? How is it calculated, if you could provide an example with numbers for both trials, please? I am not a statistician, but I am familiar with the ...
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How to convert relative risk and confidence intervals/standard error to odds ratio and confidence intervals/standard error
I am conducting a meta-analysis and have one study which reports relative risks, and several studies reporting odds ratios. I would like to convert the relative risks to odds ratios and obtain ...
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