Survival analysis compares the statistical strength of predictors for events encoded as occuring or censored in concert with a time variable. It can be parametric or non-parametric.
Questions tagged [survival]
445 questions
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Cox proportional hazard model on (burn) data
On a study is described which evaluates a protocol change in disinfectant practices in a large midwestern university medical center. Of primary interest in the study is a comparison of two methods of body cleansing. The first method, used exclusively…
Dana
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Is there a way to bound the variances estimates in the `coxme` R package?
I use the variance estimates obtained in a coxmeoutput for a further procedure:
model = coxme(Surv(time, status) ~ (0 + A | B ) + (1| B ) + strata(A) , data)
NUM = sum(unlist(model$vcoef))
However, I need the sum of the two variances estimates (NUM…
Flora Grappelli
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Calculating months of follow-up with pyears() of survival package
I want to calculate the person-time of follow-up by calendar month. In my example, I have three subjects, with different times of follow-up. I want to know if the rates of the event vary by year tertiles, so I want to sum up the time at risk they…
Jose Victor Zambrana
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Create new columns in loop based on different datasets
Here's a brief description of the data I have: Survival data from 4 separate studies that compares the survival rates among 20 groups. Each study lasted a different amount of time. For example, study 1 lasted 42 days and Study 2 lasted 50 days. …
user2813606
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Why is pval.size ignored by ggsurvplot_facet?
Why is pval.size ignored by ggsurvplot_facet()?
I am trying to change the size of the p-value text in my survival plot using ggsurvplot_facet(), but the call to pval.size appears to be ignored. If anyone can help me change p-value size in my…
Pat Taggart
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Error variable lengths differ ggsurvplot_facet
I am trying to run ggsurvplot_facet() but cannot get past Error in model.frame.default(formula = surv_object2 ~ id, data = list( :variable lengths differ (found for 'id'). Any help would be greatly appreciated.
I believe the error is in the…
Pat Taggart
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Predict event probability per factor with a coxph model
My question is a relatively simple one but I couldn't find any clear answer from the different forums.
I am running a coxph model to predict the survival of individual plants that experienced two treatments in three different sites. The individuals…
Julien Barrère
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Plot survival curves for regression employing tt and strata and frailty() - coxph in r
I have a Cox regression which employs strata() and a tt().
How can i plot this? All the usual suspects (ggsurvplot, hazard.ratio.plot) dont work for a coxph.penalformat.
Here is some dummy data:
set.seed(132456)
'dummy survival…
Juan
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Add stratification in surv.coxph for mlr library? (R)
I'm unable to add strata() anywhere in the formula when training a Cox regression using mlr's surv.coxph
Here's a rough example using lung dataset from survival package. I've arbitrarily chosen sex variable as my stratification…
haosin
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"object 'status' not found" error when using coxph in R
Whenever I get to the "coxph" function in my code it gives me the error "Error in Surv(time, status) : object 'status' not found". But I don't get that same error elsewhere. What can I do?
This is my current…
Nonya
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Surv function input - right,left or interval censored? In R
I am at the beginning of setting up a survival analysis in R.
I took a look in this book here: https://www.powells.com/book/modeling-survival-data-9780387987842/ but struggle to properly set the data up in the first place. So this is a very basic…
Juan
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Scoping with formulae in coxph objects
I'm trying to write a set of functions where the first function fits a cox model (via coxph in the survival package in R), and the second function gets estimated survival for a new dataset, given the fitted model object from the first function. I'm…
alex keil
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How to set data for R survival analysis
I'm sorry if the question looks silly, but I have a small data set which I would like to manipulate with function "survfit" of R package "survival", and, well, I don't know to set a proper dataframe usable by "survfit"; data are as follows:
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Andrew
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survival::tmerge() giving as.Date.numeric(value) error
I'm trying to tmerge some data together to do some survival analysis, but I keep getting an error.
library(survival)
library(lubridate)
df1 <- data.frame(id = "62103",
hire.date = ymd("2016-05-16"),
end.date =…
dyrland
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How to calculate individual restricted mean survival time (RMST) in R?
I encountered some issues when calculating restricted mean survival time (RMST) in R and I made some attempts.
Here is the idea that I tried to calculate the RMST by myself.
i) I fitted a cox regression model to get estimated function of h(t), and I…
Sugus
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