search for: survdiff

Displaying 20 results from an estimated 26 matches for "survdiff".

2008 Dec 04
Comparing survival curves with "survdiff" "strata" help
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....
2007 Apr 26
Extract p-value from survdiff function
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.
2012 Oct 18
looping survdiff?
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...
2012 Oct 19
Looping survdiff wonder if there''s homework involved.... Simpler for your example is to use get and subset. dat <- structure(..... as found below <- names(dat)[4:6] #variables of interest nvar <- length( chisq <- double(nvar) for (i in 1:nvar) { tfit <- survdiff(Surv(time, completion==2) ~ get([i]), data=dat, subset=(group==3)) chisq[i] <- tfit$chisq } write.csv(data.frame(, chisq)) On 10/19/2012 05:00 AM, r-help-request at wrote: > Hello, > > I am trying to set up a loop that can run the...
2005 Nov 23
survdiff for Left-truncated and right-censored data
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
2009 Aug 03
survdiff for left-truncated data?
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]]
2004 Aug 17
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...
2018 Feb 15
Fleming-Harrington weighted log rank test
> On Feb 13, 2018, at 4:02 PM, array chip via R-help <r-help at> 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 (
2018 Feb 15
Fleming-Harrington weighted log rank test
> On Feb 14, 2018, at 5:26 PM, David Winsemius <dwinsemius at> wrote: > >> >> On Feb 13, 2018, at 4:02 PM, array chip via R-help <r-help at> 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 (
2018 Feb 14
Fleming-Harrington weighted log rank test
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 (
2012 Jan 10
Lapack routine dgesv: system is exactly singular
...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...
2004 Sep 28
Validating a Cox model on an external set
...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
2002 Oct 11
automatic chi-square grouping in R
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)...
2005 Aug 28
stratified Wilcoxon available?
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
2008 Apr 09
How to estimate a hazard ratio using an external hazard function
...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)
2013 Nov 20
How to stop Kaplan-Meier curve at a time point
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
2010 Dec 20
survexp - unable to reproduce example
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...
1998 Apr 05
R-beta: loading C binaries
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...
2006 Jan 03
p-value of Logrank-Test
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
2007 May 10
getting the normal dist from the chisqr with 1df
...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]] ____________________________________________...