# How many censored data is too many for Kaplan-Meire estimate?

#### Tomomi

##### New Member
Hello there. I am new to this forum and want to ask your advice on survival-time calculation.
I have a data set which contains 60 patients (dogs).
During 36-month follow-up period, 6 patients died, and we have lost 7 patients for follow-up.
Other patients (n=47) were still alive. This means we have 54 censored samples (lost or alive).

In this case, is Kaplan-Meire analysis still accurate to conduct?
I understand that it doesn't provide median survival time because the number of patients who died is so small to calculate it.

Any comments and input would be greatly appreciated!

#### hlsmith

##### Not a robit
What question are you trying to model? If there was an exposure was it randomized?

#### Tomomi

##### New Member
All 60 dogs underwent the same surgery for tracheal collapse.

#### hlsmith

##### Not a robit
So you are not looking to control for or test any hypotheses, just report survi val, correct. If so, I don't see the harm, make sure you slap on some confidence intervals on what ever metric you report. Ideally graphically. The confidence intervals will help the review take in censoring, events, and small sample/rate outcome.

#### Tomomi

##### New Member
@hlsmith Thank you for your response.
Yes, that is correct. I just want to report a median follow-up time, the survival rate at 36 months (with CI), and survival curve with censored events.
One more question. As I said at my initial post, is it correct not to have a median survival time bc there were only 6 dogs had died during the study?

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#### hlsmith

##### Not a robit
Your last sentence has typo, but yeah - it is not uncommon to not have a median survival time if the majority survived!

#### Tomomi

##### New Member
@hlsmith Thank you for your response and confirmation about a median survival time. Is my last sentence correct now? I had left out "6" dogs in the sentence.

#### hlsmith

##### Not a robit
Yeah at the close of follow-up if only 6 dogs died then you just won't have a median survival time.