Bob Green
2014-Jun-10 06:31 UTC
[R] Recurrent analysis survival analysis data format question
Hello, I'm hoping for advice regarding how to set up a recurrent event survival analysis data file. My data consists of people released from custody, with survival time being measured as days before re imprisonment or end of the study. In the example below, id 5155 is released 5 times and jailed five times. All events are therefore true. Daysfree is the difference in days between release and return to custody. Id 7155 is released 3 times and only re-imprisoned twice, so the third event value is false. id <- c(5155, 5155,5155,5155, 7155, 7155,7155) Release <- c("29/10/10","9/01/11", "25/03/12", "15/10/13", "9/01/10", "16/12/12","29/10/13") JailNew <- c("1/12/10","01/12/11", "27/09/12", "24/01/14", "22/09/12","24/01/12","24/01/14") DaysFree <- c(24,234,134,74,709,29,64) Event <- c("true", "true", "true", "true", "true", "true", "false" ) DF1<- data.frame(id, Release, JailNew, DaysFree, Event) DF1 After speaking to a statistician today I'm not sure if I my method of formatting the data is correct. Should all time intervals be included, not just the period from release to event/end of study period. Currently period imprisoned is not counted. For example, for id 5155, would I also include 1/12/10 - 9/01/11 etc, which would be FALSE for event and have a duration of 39 days; and then include all the other similar intervals as well. The statistican thought including this additional information more closely resembled the bladder1 data in the Survival package. Any assistance is appreciated, Regards Bob
Andrews, Chris
2014-Jun-10 19:02 UTC
[R] Recurrent analysis survival analysis data format question
I wouldn't consider the person at risk for re incarceration if he is currently imprisoned. So I wouldn't use those intervals as part of the response variable. Perhaps time in custody would be a covariate used to model the time until re incarceration. One variable that is commonly needed for analysis of recurrent data is the number of previous events. It can be used to, e.g., stratify. Chris -----Original Message----- From: Bob Green [mailto:bgreen at dyson.brisnet.org.au] Sent: Tuesday, June 10, 2014 2:32 AM To: r-help at r-project.org Subject: [R] Recurrent analysis survival analysis data format question Hello, I'm hoping for advice regarding how to set up a recurrent event survival analysis data file. My data consists of people released from custody, with survival time being measured as days before re imprisonment or end of the study. In the example below, id 5155 is released 5 times and jailed five times. All events are therefore true. Daysfree is the difference in days between release and return to custody. Id 7155 is released 3 times and only re-imprisoned twice, so the third event value is false. id <- c(5155, 5155,5155,5155, 7155, 7155,7155) Release <- c("29/10/10","9/01/11", "25/03/12", "15/10/13", "9/01/10", "16/12/12","29/10/13") JailNew <- c("1/12/10","01/12/11", "27/09/12", "24/01/14", "22/09/12","24/01/12","24/01/14") DaysFree <- c(24,234,134,74,709,29,64) Event <- c("true", "true", "true", "true", "true", "true", "false" ) DF1<- data.frame(id, Release, JailNew, DaysFree, Event) DF1 After speaking to a statistician today I'm not sure if I my method of formatting the data is correct. Should all time intervals be included, not just the period from release to event/end of study period. Currently period imprisoned is not counted. For example, for id 5155, would I also include 1/12/10 - 9/01/11 etc, which would be FALSE for event and have a duration of 39 days; and then include all the other similar intervals as well. The statistican thought including this additional information more closely resembled the bladder1 data in the Survival package. Any assistance is appreciated, Regards Bob ********************************************************** Electronic Mail is not secure, may not be read every day, and should not be used for urgent or sensitive issues