Richard,

Your sample data does not show it, but can an ID have more than one admission?

Jack

Jack Clark Research Analyst phone: 410-455-6256 fax: 410-455-6850 jclark@hilltop.umbc.edu

University of Maryland, Baltimore County Sondheim Hall, 3rd Floor 1000 Hilltop Circle Baltimore, MD 21250

Confidentiality Notice: This e-mail may contain information that is legally privileged and that is intended only for the use of the addressee(s) named above. If you are not the intended recipient, you are hereby notified that any disclosure, copying of this e-mail, distribution, or action taken in reliance on the contents of this e-mail and/or documents attributed to this e-mail is strictly prohibited. If you have received this information in error, please notify the sender immediately by phone and delete this entire e-mail. Thank you.-----Original Message----- From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of Richard Van Dorn Sent: Wednesday, July 30, 2008 7:33 AM To: SAS-L@LISTSERV.UGA.EDU Subject: Help with excluding events between two dates

Hello all.

I have data that look like the following:

ID SERVICE DOS DOA DOD 1 Blood 08FEB1999 . . 1 Blood 09FEB1999 09FEB1999 11FEB1999 1 Blood 10FEB1999 . . 1 Blood 11FEB1999 . .

Service is the service provided, DOS is the date of that service, DOA is the date of admission to the hospital and DOD is the date of discharge from the hospital.

I need to retain all services that took place out the hospital. For example, in the data above, the only outpatient service was a blood draw on February 8, 1999. All other blood draws took place in the hospital.

Thank you. Richard