All Questions
13 questions with no upvoted or accepted answers
2
votes
0
answers
40
views
Cox-Hazard Ratio differences in Software suits; Manual calculation
Working in clinical research my task is to calculate the Hazard ratio, better to check the calculations of someone else. This first calculation was based on ARM=(3 different treatments) with only t=(...
- 117
2
votes
0
answers
1k
views
Survival Analysis on Telecom Churn in R
I am working on Telecom Churn problem and here is my dataset.
http://www.sgi.com/tech/mlc/db/churn.data
Names - http://www.sgi.com/tech/mlc/db/churn.names
I'm new to survival analysis.Given the ...
- 91
2
votes
0
answers
167
views
Survival Analysis--All variables failed the proportionality test. What next?
I am building a cox survival analysis model with a retailer's transaction data. Almost all the variables have failed the proportionality test. Can I continue with the Cox model? Should I build a ...
- 21
1
vote
0
answers
395
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How does the "ZPH" option of PROC PHREG in SAS 9.4 works?
As I saw in SAS 9.4 documentation, the "ZPH" option in PROC PHREG statement requests diagnostics based on the weighted Schoenfeld residuals for checking ...
- 123
1
vote
1
answer
136
views
Reformat data problem for Cox model in SAS
I am relatively new to SAS. Currently I am taking survival analysis course, and I am really stuck on reformatting a data into 'counting process' (start, stop) form for fitting a Cox regression model ...
1
vote
0
answers
391
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Estimated Survival Discrepancies: Kaplan-Meier vs an Extended Cox Regression
I have a massive data set of about 25000 pancreatic cancer patients; extremely quick and depressing mortality rate. I'm interested in survival differences between three groups--no treatment, ...
- 123
1
vote
0
answers
259
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Poor survival analysis model fit with Gronnesby and Borgan
I have been experiencing issues with model fit. In my example, I have set up a time-varying (counting method) survival analysis model (Cox regression with ...
- 21
1
vote
0
answers
125
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Cox regression problem with time varying covariates
I was working on a cox regression problem and was refering to this link:
http://support.sas.com/documentation/cdl/en/statug/63347/HTML/default/viewer.htm#statug_phreg_sect050.htm
I have few ...
- 31
0
votes
0
answers
14
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Recurrent event model - time to multiple medication discontinuations
I am using the following recurrent event model (counting process style input) to plot cumulative mean frequency of multiple medication initiations. Just like patients in the study can initiate ...
- 1
0
votes
0
answers
43
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Marginal structural model using PROC PHREG
I would like to fit a marginal structural model to account for treatment switching during follow-up.
I found a great paper on how to do this in R: https://www.sciencedirect.com/science/article/abs/pii/...
- 635
0
votes
1
answer
368
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How to create KM curves with time-dependent covariate
Some patient received an treatment as treated group and some did not as control group. In order to consider "immortal time bias", I coded the treatment as a time-dependent covariate. Could ...
0
votes
0
answers
2k
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Interaction with restricted cubic spline - comparison between SAS and R
When performing the same cox-regression in SAS and i R (including and interaction with a 3 knot restricted cubic spline), I receive different parameter estimates (i.e on age_spline 2). In my example ...
- 1
0
votes
0
answers
417
views
How to estimate the n-year Hazard Ratio from PROC PHREG
Dear SAS users in the CV community:
I am using the sample data publicly available at:
https://stats.idre.ucla.edu/wp-content/uploads/2016/02/whas500.sas7bdat
The tutorial is found here along with a ...
- 101