I have a large data set where some observation-periods are right censored (no event observed), others are interval censored (event observed but timing is uncertain), and some events fall into the observation-period.
- we have individuals with year of birth between 2000 and 2018
- each individual can have at most one event. There is only one type of event.
- we know the timing of events that occurred in the period 2009-2018
- events that occurred before the year 2009 are all registered in 2008. For individuals with birth year before 2009 who also had and event before the year 2009, we therefore only know that an event happened between the year of birth and 2008. (interval censoring)
- we have no knowledge about events that occurred after 2018 (right censoring)
My understanding is that this data can be described as interval-censored data.
Another important characteristic of the data is that observations are clustered: Events are observed in strata (children in the same family), and the goal is to estimate the effect of within-strata variation of an exposure on occurrence of events with a fixed-effects model. To implement a fixed-effects cox model I need to use stratified baseline hazards.
The challenge is that I would like to do calculate a semi-parametric Cox proportional hazards regression (e.g.
coxph from the survival package) with stratified baseline hazards, but AFAIK
coxph does not work with survival objects that describe interval censored data. (I could use parametric models implemented in the
survreg function, but I'd like to try the cox model first).
I'd be glad about any pointer to packages that allow to estimate cox models with interval censored data while also estimating strata-specific baseline hazards and robust standard errors in R. (As far as I can this is possible in the newest Stata 17).
PS: There is the icenReg package which supports cox regressions for interval-censored data, but I could not find information about stratification and robust standard errors in the package documentation. I therefor assume that this package cannot deal with my data.