search for: survdiff

ExpeRts, I''m trying to compare three survival curves using the function "survdiff" in the survival package. Following is my code and corresponding error message. > survdiff(Surv(st_months, status) ~ strata(BOR), data=mydata) Error in survdiff(Surv(st_months, status) ~ strata(BOR), data = mydata) : No groups to test When I check the "strata" of the variable....

Hi list, I want to use the p-value from the survdiff function (package survival) to reuse within a function in a Kaplan-Meier plot. The p-value is somehow not a component of the value list ?! Thanks in advance -- A. Goralczyk G?ttingen, Ger.

Hello, I am trying to set up a loop that can run the survdiff function with the ultimate goal to generate a csv file with the p-values reported. However, whenever I try a loop I get an error such as "invalid type (list) for variable ''survival_data_variables[i]". This is a subset of my data: structure(list(time = c(1.51666666666667, 72, 7...

...me wonder if there''s homework involved.... Simpler for your example is to use get and subset. dat <- structure(..... as found below var.to.test <- names(dat)[4:6] #variables of interest nvar <- length(var.to.test) chisq <- double(nvar) for (i in 1:nvar) { tfit <- survdiff(Surv(time, completion==2) ~ get(var.to.test[i]), data=dat, subset=(group==3)) chisq[i] <- tfit$chisq } write.csv(data.frame(var.to.test, chisq)) On 10/19/2012 05:00 AM, r-help-request at r-project.org wrote: > Hello, > > I am trying to set up a loop that can run the...

dear all, I would like to know whether survdiff and survReg function in the survival package work for left-truncated and right-censored data. If not, what other functions can i use to make comparison between two survival curves with LTRC data. thanks for any help given sing yee

Hi Does anyone know if there is a function like survdiff which can also handle left-truncated and right-censored data? When I use it on left-truncated and right-censored data I get an error message saying Right censored data only. Many thanks Rajen [[alternative HTML version deleted]]

Hello, As I am quitte an ignorant user of R, excuse me for any wrongfull usage of all the terms. My question relates to the statistics behind the survdiff function in the package survival. My textbook knowledge of the logrank test tells me that if I want to compare two survival curves, I have to take the sum of the factors: (O-E)^2/E of both groups, which will give me the Chisq. If I calculate this by hand, I get a different value than the one R...

> On Feb 13, 2018, at 4:02 PM, array chip via R-help <r-help at r-project.org> wrote: > > Hi all, > > The survdiff() from survival package has an argument "rho" that implements Fleming-Harrington weighted long rank test. > > But according to several sources including "survminer" package (https://cran.r-project.org/web/packages/survminer/vignettes/Specifiyi...

> On Feb 14, 2018, at 5:26 PM, David Winsemius <dwinsemius at comcast.net> wrote: > >> >> On Feb 13, 2018, at 4:02 PM, array chip via R-help <r-help at r-project.org> wrote: >> >> Hi all, >> >> The survdiff() from survival package has an argument "rho" that implements Fleming-Harrington weighted long rank test. >> >> But according to several sources including "survminer" package (https://cran.r-project.org/web/packages/survminer/vignettes/S...

Hi all,? The survdiff() from survival package has an argument "rho" that implements Fleming-Harrington weighted long rank test.? But according to several sources including "survminer" package (https://cran.r-project.org/web/packages/survminer/vignettes/Specifiying_weights...

...t this, can I cannot understand how the explanations apply to what I am trying to do. I am trying to do Log_rank Survival analysis, I have included tables and str command, is it a factor/integer problem? If so how do I correct this, as all my attempt to recode the data have failed. > survdiff(Surv(f2$days.alive , f2$censored)~group, data=f2) Error in drop(.Call("La_dgesv", a, as.matrix(b), tol, PACKAGE = "base")) : Lapack routine dgesv: system is exactly singular > head(f2) group days.alive censored 1 PRI_CAS_5_NODU 1826 1 2 PRI_CA...

...the Cox model to predict survival for the test set, and obtained individual predictions for survival time, with standard error for each test sample. Each of these cases has an actual survival time, some censored. How can we decide whether the Cox model has been validated or not? I was suggested survdiff in the survival package, but survdiff works between curves; am not sure how I could use it (I have a predicted curve for each curve, but no ''observed curve'' - the only observation is death or censoring at time x) Thank you all so much! Min-Han Tan Van Andel Institute

I''m doing some chi-square tests, and I recall some arbitrary rule that says each band must have at least 5 events in order for the test to be meaningful. Is there some way to do the banding automagically in R ? For instance, in the following survdiff, I''m trying to see if ADL affects survival. But when ADL=3,5 and 6, the number observed is too little. Anyway for me to tell R how to group them ? Like "R, combine ADL=5 and ADL=6, and redo the test" ? ----------- Call: survdiff(formula = Surv(days, status) ~ adl, data = nu)...

Dear All, is there a stratified version of the Wilcoxon test (also known as van Elteren test) available in R? I could find it in the survdiff function of the survival package for censored data. I think, it should be possible to use this function creating a dummy censoring indicator and setting it to not censored, but may be there is a better way to perform the test. Thanks, Heinz T??chler

...individual data, but grouped data that allows to obtain a hazard function. I am wondering if there is an R function that allows to obtain a hazard ratio of the two hazard funtions (under the proportionality assumption) taking into account the censoring of the data? I am aware of survexp and survdiff functions, but I am not sure if that is the best way to do what I need. Any help will be highly appreciated. Montse Rue Department of Basic Medical Sciences University of Lleida (Spain)

Hello R users I have a question with Kaplan-Meier Curve with respect to my research. We have done a retrospective study on fillings in the tooth and their survival in relation to the many influencing factors. We had a long follow-up time (upto 8yrs for some variables). However, we decided to stop the analysis at the 6year follow up time, so that we can have uniform follow-up time for all the

Dear All, when I try to reproduce an example of survexp, taken from the help page of survdiff, I receive the error message "Error in floor(temp) : Non-numeric argument to mathematical function" . It seems to come from match.ratetable. I think, it has to do with character variables in a ratetable. I would be interested to know, if it works for others. With an older version of sur...

Can anybody explain what is happening? I am using RedHat Linux 5.0 with the latest Martyn Plummer RPM's installed, both at home and at the office. At home "survival4" is (still) working OK. At the office all the components ('survfit', 'survdiff', 'coxph, etc..) stop with an error message that they can't 'find' or 'load' the C binaries: i.e. '.C("survfit2",....)'. Immediately after installing everything worked OK , I still have the saved objects to prove it. But I obviously did something wro...

Hello! I want to compare two Kaplan-Meier-Curves by using the Logrank-Test: logrank(Surv(time[b], status[b]) ~ group[b]) This way I only get the value of the test-statistic, but not the p-value. Does anybody know how I can get the p-value? Thanks in advance! Verena Hoffmann

...ring" act.surv.time<-pmin(m[,"censoringTime"],m[,"survivalTime"]) m<-cbind(m,act.surv.time) print(m) write.table(m,”clipboard”,sep=”\t”,col.names=NA) print(“.................”) print(“the logrank test”) b=data.frame(m) c= survdiff(Surv(act.surv.time,censoring)~treatmentgrp,data=b) print(c) s=s-1 print(“...............................................................”) } --------------------------------- [[alternative HTML version deleted]] ____________________________________________...