It seems like the dates are not in the correct format. How did you convert the dates? I'd import the original dataset leaving the date as a string variable, then do the following:
gen date2=daily(date, "DMY")
format date2 %td
drop date
ren date2 date
And now the previous code should work
_________________________
Jorge Eduardo Pérez Pérez
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Gary Walker
Sent: sábado, 11 de julio de 2009 05:21 p.m.
To: [email protected]
Subject: Re: st: RE: Gap in treatment
Actually I forgot I converted the dates before importing into stata.
Now it is like this:
Patient days chemo drug
A 45 X
A 6745 Y
A 645 X
B 345 Z
B 343 X
C 5667 Y
C 123 X
C 5 Z
When I try:
sort patient days
it is not in the correct order. it lists them like this:
101
178
201
255
13
54
78
Why is it not sorting them correctly?
On Sat, Jul 11, 2009 at 3:11 PM, PEREZ PEREZ JORGE
EDUARDO<[email protected]> wrote:
> Make sure your date has the proper format (i.e %td), then:
>
> sort patient date
> by patient: gen gap=date[_n]-date[_n-1]
> by patient: egen maxgap=max(gap)
>
> Hope this helps,
> _________________________
> Jorge Eduardo Pérez Pérez
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On Behalf Of Gary Walker
> Sent: sábado, 11 de julio de 2009 04:45 p.m.
> To: [email protected]
> Subject: st: Gap in treatment
>
> I have a dataset of each administration of chemotherapy for a number
> of patients, i.e.:
>
> Patient date chemo drug
> A 7/1/2009 X
> A 4/1/2009 Y
> A 1/1/2008 X
> B 7/1/2009 Z
> B 1/1/2008 X
> C 7/1/2009 Y
> C 4/1/2009 X
> C 1/1/2008 Z
>
> I want to calculate the biggest gap in treatment for each patient. In
> other words, what was the maximum amount of time between treatments
> for each patients. Any ideas on how to do this?
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
--
Gary Walker
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
