BookmarkSubscribeRSS Feed
SarahW13
Obsidian | Level 7

Hello all! I have a question about how to do Cox regression for matched cases and controls. In my example, I have 2 controls matched to each case. I used the code from this article to generate my dataset of matched cases and controls: http://www2.sas.com/proceedings/sugi29/173-29.pdf

 

However, now I am stuck at figuring out how to actually run the analysis. I have my original dataset that has all of the covariates that I need, and I have the new dataset that has the id's of the controls, id's of the matched cases, and the variables that I used to match the cases & controls (in this case, age).

 

In my original dataset, this is what I have:

id                 age               treatment               survival             survival_censor

1                  57.1              0                            3.41                  1

2                  38.1              0                            2.05                  1

3                  42.5              0                            1.95                  0

100              57.4              1                            3.10                  1

101              57.0              1                            5.38                  0

120              38.2              1                            0.95                  0

125              38.9              1                            4.41                  0

105              43.9              1                            3.41                  0

132              41.3              1                            2.37                  0

 

Below is an example of what I have in the new dataset that has case:control matches (1:2):

 

case_id       control_id        case_age        control_age     rand_num      num

1                 100                  57.1                57.4                 0.56778         1

1                 101                  57.1                57.0                 0.56778         2

2                 120                  38.1                38.2                 0.23116         1

2                 125                  38.1                38.9                 0.23116         2

3                 105                  42.5                43.9                 0.95096         1

3                 132                  42.5                41.3                 0.95096         2

 

I would like to run a Cox regression comparing the survival between the matched cases and controls, but I have the actual case-control pairings in one dataset and the survival info (plus other covariates that I need to adjust for) in a separate dataset.

 

Does anyone have any advice on the next steps I need to do?

Thanks!

 

1 REPLY 1
SarahW13
Obsidian | Level 7

I thought I would check again to see if anyone has thoughts on this. Would cox regression even be appropriate in this case, or would I need other methods (eg, conditional logistic regression) to compare survival between the matched cases and controls? Any guidance would be much appreciated.

sas-innovate-2024.png

Don't miss out on SAS Innovate - Register now for the FREE Livestream!

Can't make it to Vegas? No problem! Watch our general sessions LIVE or on-demand starting April 17th. Hear from SAS execs, best-selling author Adam Grant, Hot Ones host Sean Evans, top tech journalist Kara Swisher, AI expert Cassie Kozyrkov, and the mind-blowing dance crew iLuminate! Plus, get access to over 20 breakout sessions.

 

Register now!

What is ANOVA?

ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.

Find more tutorials on the SAS Users YouTube channel.

Discussion stats
  • 1 reply
  • 1280 views
  • 0 likes
  • 1 in conversation