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Re: st: Mixed continuous and interval censored time-to-event analysis
From
Steve Samuels <[email protected]>
To
[email protected]
Subject
Re: st: Mixed continuous and interval censored time-to-event analysis
Date
Thu, 4 Oct 2012 16:57:50 -0400
The following commands can take mixture of interval censoring and uncensored
data( the proper term for what you are calling "continuous").
-intreg-
-intcens- (SSD)
-stpm- (SSC)
They work, because each assumes a parametric model. For parametric models, the likelihood contributions of different types of observations
(uncensored, left-censored, right-censored, interval-censored, late
entry) are well-defined. The likelihood analysis of parametric models is
covered in every text, and you can find some good ones in the Stata
Manual references to -streg-.
The lag between the actual failure event and hospital detection means
that the hospital events are interval-censored. To ignore the lag, you
must have strong evidence that it is "short". A better approach, still
more "exact" in comparison to questionnaire-based detections, is to treat
the hospital-based admissions as interval censored, but with interval lower
endpoints based on theory or on empirical knowledge.
Another issue: if failure is associated with hospitalization,
then the hospital-detected events are a biased sample of all events.
Steve
On Oct 3, 2012, at 10:26 AM, MacLennan, Graeme wrote:
Dear Statalist, I have data on time to an event, the event is "failure" in a randomised controlled trial. Information on failure is collected through two channels. Firstly, annual questionnaires where failure is defined as being below a certain cut-off on a self-reported outcome measure, although reported annually this failure will have occurred at some point between the last non-failure questionnaire the failure questionnaire, I consider this to be interval censored time-to-event data. Secondly failure data is captured through routine data sources on hospital readmissions, and as such is a more exact representation of failure time (putting aside any concerns one might have about lag between time of failure and admission to hospital), and I consider this to be continuous time-to-event data.
A clear strategy is to aggregate the continuous data up to interval censored data and use appropriate methods, but this seems like a waste of information to me. However, after some initial digging about I can't find any pointers, so my question is do the list members know of any literature on this, particularly with Stata in mind?
Regards, Graeme.
The University of Aberdeen is a charity registered in Scotland, No SC013683.
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