Appreciate any help you can give. I'm interested in determining UTD status of a cohort. I inherited code where I can determine UTD status by a certain age. I want to compare freq UTD at one date vs. a later date, using same age criteria (EX:  must receive 4th dose by 4th birthday or must receive 5 doses at any age). Here is the code I have which I tweaked based on the code I inherited: ...data is imported and dates are converted to sas dates; *--define cutoff date; cutoff='31-AUG-2010'd; *--determine if kids received 4th dtp dose or after 4th bday (calculated as 1461) or 5 doses at any age; 1461<=(dtp4-bdate)<=cutoff or 0<=(dtp5-bdate)<=cutoff then cutoff_dtp=1; .... I run the program a 2nd time using a later cutoff date, below and compare the frequency where cutoff_dtp=1 cutoff='15-FEB-2011'd;   But I am getting the same freq of the UTD status variable 'cutoff_dtp'.  It could be possible that no additional kids got vaccinated between the first date and later date. For one kid: SAS dates based on Aug 31, 2010 cutoff: bdate =16641 dtp4=17145 cutoff= 18505 SAS dates based on Feb 15, 2011 cutoff: bdate =16641 dtp4=17145 cutoff= 18673 Is this the right way to do it or am I missing something?  Thanks! ... View more

G'day. I have a large file (>5000 obs). Each child has immunization doses for they childhood vaccines they received. I inherited a data checking program that identifies which doses in the dose series (i.e, 3 Hepatitis B Doses required) are out of order. How do I get the dates in order (earlier date first, later date next, and latest date last: school          childnum                hepb1                hepb2                hepb3 P001                    001            01/25/2008          10/24/2007         07/25/2008    (this should be hepb1:  10/24/2007, hepb2:  01/25/2008, hepb3:  07/25/2008) P001                    002             10/11/2008          07/10/2008        04/10/2007  (this should be: hepb1:  04/10/2007, hepb2:  07/10/2008, hepb3:  10/11/2008) P002                    001            11/15/2007            05/15/2008        02/11/2008  (this should be: hepb1:  as is, hepb2:  02/11/2008, hepb3:  05/15/2008) etc... Any help you can give is much appreciated. Thanks! ... View more