topic Re: proc lifetest Brookmeyer-Crowley confidence interval for median: conftype=? in Statistical Procedures

proc lifetest Brookmeyer-Crowley confidence interval for median: conftype=?

fengyuwuzu — Wed, 21 Jul 2021 22:57:08 GMT

since SAS 9.2, the default CONFTYPE=LOGLOG in proc lifetest.

if I want calculate BrookMeyer-Crowley confidence interval for the medial survival, must I set CONFTYPE = LINEAR?

How do I know the confidence interval I got is Brookmeyer-Crowley CI?

Re: proc lifetest Brookmeyer-Crowley confidence interval for median: conftype=?

sbxkoenk — Wed, 21 Jul 2021 23:04:53 GMT

Look here:

Brookmeyer and Crowley Confidence Intervals?
Posted 11-02-2019 11:00 PM
https://communities.sas.com/t5/Statistical-Procedures/Brookmeyer-and-Crowley-Confidence-Intervals/td-p/601198

Kind regards,

Koen

Re: proc lifetest Brookmeyer-Crowley confidence interval for median: conftype=?

OsoGris — Fri, 23 Jul 2021 11:16:32 GMT

The LIFETEST documentation under Details => Breslow, Fleming-Harrington and Kaplan-Meier Methods specifies that all the confidence intervals are based on Brookmeyer and Crowley. Here is the paragraph from the documentation:

"Brookmeyer and Crowley (1982) have constructed the confidence interval for the median survival time based on the confidence interval for the S(t). The methodology is generalized to construct the confidence interval for the 100pth percentile based on a g-transformed confidence interval for S(t) (Klein and Moeschberger 1997). You can use the CONFTYPE= option to specify the g-transformation. "