Questions tagged [censoring]
The process of censoring yields data w/ only partial information. The most common example of censoring is *right censoring* in survival analysis, where the time until the event occurred is only known to be longer than some duration because the event had not occurred when the study ended.
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Survival analysis if one group is all censored?
I'm analyzing 2 groups where all of the subjects in one group are still alive, i.e. one group is entirely right-censored. The other group is a mix of censored and uncensored. Is a Cox proportional ...
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Difference between left censoring and interval censoring
I'm dealing with some medical data which is made up of all admissions to hospital in a certain area, where each row is one patient admission alongside the various tests and demographic data done. Also ...
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Predicting hazard function before left truncation point in survival analysis
I want to know if it is not only possible to handle left-truncation of data in a survival model, but to know/predict the hazard function (probability of event) before the start point, i.e. the point ...
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Anderson Gill counting process for recurrent events: covariates?
I have a dataset I made using Anderson-Gill counting process template. i.e each person appears in $N+1$ rows where $N$ is the number of events they had. $N$ rows for the $N$ events and 1 row for the ...
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How do i generate separate survival data which is also left-censored and interval-censored?
I am trying to generate both left-censored and interval-censored datasets which both have the same features. I wish to fit and compare a cox model, Aalen's additive model and an Accelerated failure ...
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What is pseudocomplete data?
Skimming Huang et al 2019 I see references to a term "pseudocomplete-data" that I am not familiar with. It looks like they are dealing with a data censoring problem which they approach with ...
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When fitting a Cox proportional hazards model, should we drop any observations that are right-censored at zero?
Consider the standard Cox proportional hazards setting with non-informative censoring. (See https://web.stanford.edu/~lutian/coursepdf/unitcox1.pdf for example.)
If our observations are triples $(Z_i, ...
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Simple unbiased mean estimator for censored data
Suppose I have an i.i.d. random sample of size $n$ s.t. $X_i \sim \mathcal{N}(\mu, \sigma^2)$ for all $i$. But suppose my observed sample is left censored, such that any $x_i$ observation is replaced ...
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Simulating survival data to reflect existing complex dataset and censoring proportions
I am trying to compare the impact of different censoring proportions on different survival analysis models. For that, I plan to do a simulation study and then apply the best model on real-life child ...
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[Survival Analysis]: Handling Data Acquired after an Event Occurs
I am conducting a survival analysis to examine the impact of a set of covariates X on the time-to-event Y. However, I have collected data on participants even after the event has occurred, where the ...
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Expectation of Wordle score
I am interested in determining the expectation for a person's wordle score. If the person guessed the word every time, this would be straight-forward using simple expected value calculations. ...
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Unequally right-censored survival analysis
I'm trying to do a survival analysis and I want to know how to handle unequal right-censorship.
Essentially, people enter the trial at different ages and exit either at death or at the end of the ...
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Survival analysis: how to determine time at which covariates are obtained?
I'm interested in predicting when a customer will churn, after they've turned a certain age (in this case, age 18, but this could really be any number).
This piece is critical: given the domain being ...
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Defining states in Multi-State model
I am looking to build a multi state model some packages for instance in R are for panel or intermittently observed data (msm ...
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How should I code a laboratory variable that may occasionally have "under X.XX" type of character data as a continuous numeric variable?
A typical laboratory in my region may give a result to e.g. the C-reactive protein (CRP) blood test in the following way (I'll omit the units here):
if the result is under <10, they'll give the ...
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Binary and Censored Data: What are the advantages and disadvantages of considering binary data as a completely censored random variable?
(Full disclosure: I'm trained as a physicist, so maybe the answer to this question exists and I just need to be pointed in the right direction).
I have been working with a material properties data set ...
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Effects of right-censoring on Poisson IRR estimates
I have some time-to-event data with right-censoring.
Details Added: Each subject is followed up until first event (no recurrent events) or loss to follow-up. Let's assume there are no competing risks.
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How to handle intermittent missing visits in marginal structural model?
The reference papers for marginal structural models only talked about handling monotone censoring using IPCW.
How to deal with intermittent missing visits? Does it make sense to use available visits ...
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Logistic modeling with censored predictors
What are not-too-complex methods to perform logistic modeling if some of the predictors are right-censored?
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Can I apply a time dependant covariate to a cox regression with calendar-based time scale using data with staggered entry
I have a retrospective study evaluating the effectiveness of an intervention in reducing COVID infections on subgroup of patients. Using a control and intervention group, I was hoping to set a time-...
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Confused about the censoring procedure in Helsel (2012) book
Reading Helsel STATISTICS FOR CENSORED ENVIRONMENTAL DATA USING MINITAB AND R,
at page xviii the author writes:
The Figure i4 shows concentration (y) levels versus distance (x)
downstream. What ...
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Data with rare censoring
Scenario: Rats with condition and treatments. The response measurement is a gold standard measure of the condition. However, uncommonly, rats can die during the study. That means, technically, those ...
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Censored below and above
I thought I understood the intuition behind censoring but I need to be perfectly clear about one thing which confuses me.
In my course book I only have the example of censoring from below:
$P(y=1) = P(...
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Right censored data in survival analysis
Hello I'm new to survival analysis and I have a question about right censored data processing.
For patient B, he survived through the entire study time. Therefore, we need to use the study end date ...
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Performing PCA on left-censored data (non-detects)
I am looking for some guidance (published or otherwise) on performing PCA on left-censored environmental data (where data above an instrument's detection limit is reported). Any help is appreciated.
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survreg not appropriate for double-censored data?
I'm consulting with a local quantitative person about some data, it's double-censored. Left censored is below limit of quantitation. Right censored is saturation of the assay. I want to regress it ...
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Survival analysis with only censored event times?
I have a dataset with destructive follow-up. That is, with a population starting at time 0, we are taking out a proportion at predetermined time points to see whether the event has occurred to them. ...
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mean and MSE of Interval censored data
I have been handed data that is interval censored where left censoring is limit of detection and right censoring is saturation of the assay. How do I estimate the means and mean standard errors of ...
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Predictions from parametric left-censored gaussian model (Tobit) look odd
I have some left-censored assay data. Several points in he response variable are below the assay's detection limit. I ran a Tobit model on the data, so far, so good. However, when I wanted to plot the ...
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Right-censoring Survivability with Custom Likelihood Function
I am having bit of difficultly understanding the process of using censored data. I know there are plenty of R packages that can do this for the usual two-parameter Weibull likelihood formula, but I ...
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Censor time-dependent Cox proportional
I am conducting a study to check whether a drug causes fractures, and I am using time dependent Cox PH model.
My question is regarding the follow-up time when stratifying. Let's say that we want to ...
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How to deal with survival analysis when censoring time depends on a covariate
I'm performing survival analysis on time to drop out of a certain program. However, the censoring of each case depends heavily on the length of the program. For example, some programs only last 3 ...
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How to account for right-censored data in a hypothesis test
Right censoring was not a major issue in my prior research on education because I was modeling outcomes like grades and graduation rates where all participant results occur on the same day.
But now I ...
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Comparing a multi-dose drug to no drug exposure in a cohort study: Censoring events between doses
I am interested in assessing the association between the two doses of a dietary supplement on an event of interest.
The primary exposure is 'two doses of the supplement', and the comparator is 'no ...
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Hazard or survival function for data with different right-censor timings and different starting periods
I have 15 years of data of patients (2001-2015). T0 differs between them, i.e. the starting year for the survival period is strongly heterogenous. I want to model their survival rate, i.e. what is the ...
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A predictor that "becomes" categorical when larger than a cutoff
I have a dataset where a predictor can have 2 states - if it's in state 1, then the value is always the same. If it's in state 2, then the value is continuous and changes. An example to this can be ...
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Left truncation or left censoring?
I am conducting a study in which I analyse the time to opt out after the free trial is ending. I have individuals who sign up for a free membership-trial period. At some point the period is ending and ...
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How to deal with randomly censored data for survival analyses
I have data across 8 different time-points that is both left, right, and interval censored (also randomly censored) that I am trying to use to conduct a survival analysis. The left-censoring should ...
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Why do I get so many NA's in my Cox proportional hazards model summary output?
I have tried to run the following Cox proportional hazards model where the dependent variable is Latency (time to a particular event), Censor denotes whether the event happened or not (1 = Yes, 0 = No)...
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Likelihood function for Type I censoring
I'm reading the textbook Survival Analysis: Techniques for Censored and Truncated Data by Klein and Moeschberger, and in Chapter 3.5 it says
Data from experiments involving right censoring can be ...
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Time to event = 0 in survival analysis?
In survival analysis, is it appropriate to have a time to event value of zero for a subject(s). For example, the subject experiences the event on the same date as their date of entry. Does this cause ...
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Censoring in GAMLSS
I have some observations $y$ which have only few negative values $y_i\in (-\infty,0)$ and mostly non-negativ values, i.e. $y_i\in [0,\infty)$. I would like to estimate a censored logistic ...
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Censoring on a different measurement?
This is a split-off from a different question about right-censored data. I think that one has been handled nicely. However, there is a corollary. In addition to analysis of time to complete a task ...
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Modeling semicontinuous data with upper bound?
I've got a data set from a timed mouse behavioral test. The test ends either when the mouse succeeds the trial or 60 seconds have elapsed. The time is recorded to failure/end. The PI thinks that it's ...
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What is independent censoring and what are its assumptions?
I'm reading the Introduction to Statistical Learning book. In chapter 11 (Survival Analysis, page 463), the authors state:
In general, we need to assume that the censoring mechanism is
independent: ...
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Survey participation date as censoring date in time-to-event analysis?
I have data coming from a survey which was collected during several months (let's assume November 2019 to February 2020). The survey collects self-reported data. The data contains the date of an event ...
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MLE for censored multivariate normal data?
Suppose I have $q$ censored covariates, say $X_1, \ldots, X_q$ which are all left-censored with censoring values $\mathbf{d} = d_1, \ldots, d_q$. If I assume that the $X_i$ are from some multivariate ...
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Using survival analysis parameters from multilevel model as a workaround for censored predictor?
I am interested in predicting psychopathology development over time using survival parameters from the survival model.
I have data collected using ESM in daily life during which individuals reported ...
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Calculating functions of truncated and censored normal variables
I am trying to understand why lines (1) and (2) give the same result
set.seed(2525);
n <- 1e6; X <- rnorm(n)
Lines (1) and (2)
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Methods to estimate bivariate survival function under *bivariate* censoring
I am looking at the relation between two time-to-event variables subject to censoring. The seminal work from Lin and Ying is unfortunately paywalled (https://www.jstor.org/stable/2337178), but I ...
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