About shrutisd0

shrutisd0 · ‎05-24-2023

I have a 3:1 nested case control matched sample dataset with match_id assigned per group id match_id event 1 1 0 4 1 0 9 1 0 10 1 1 5 2 0 11 2 0 12 2 0 13 3 1 8 3 0 16 3 0 17 3 0 I want to remove observations who have less than 4 of the same match_id (in this example observations with match_id=2).

shrutisd0 · ‎03-21-2023

I am trying to create a new variable called "stroke visit" using the information below. I have the date of stroke and visit numbers available. The stroke visit would be closest to the date of stroke (preferably before the latest visit) e.g. for ID 2 the visitnum should be "3". id stroke dateofstrk visitdate visitnum 1 0 . 11/1/2022 1 1 0 . 12/1/2022 2 1 0 . 1/1/2023 3 2 1 12/25/2022 11/1/2022 1 2 1 12/25/2022 12/1/2022 2 2 1 12/25/2022 1/1/2023 3 3 1 11/13/2022 11/1/2022 1 3 1 11/13/2022 12/1/2022 2 3 1 11/13/2022 11/1/2023 3

shrutisd0 · ‎04-21-2021

Thanks @ballardw The visits are set for all patients to 10 hence there is no "visit" variable in the dataset. Here's an example of the data: data have; input id $ age diab; datalines; abc 25 1 abc 26 1 abc 28 1 abc 29 2 abc 30 2 abc 32 2 abc 33 2 abc 35 2 abc 36 2 abc 37 2 bcd 22 1 bcd 23 1 ; For the data step, this was the only code I tried. data experiment; set have; by age; if diab in (1,3,4) then cross_age=last.age; else if diab=2 then cross_age=first.age; run; value of diab: 1=non-diabetic 2=diabetic 3=pre-diabetic 4=unknown

shrutisd0 · ‎04-21-2021

Hi! I am trying to create a new cross-sectional age variable from the existing longitudinal age variable based on the patient's diabetes status during 10 visits. If the patient is non-diabetic, pre-diabetic or unknown through all the visits then age of patient will be the last age recorded, if the patient is diabetic at visit 5 then age of patient will be age when the patient was first recorded as diabetic (i.e. age at visit 5) Here's what i attempted. if diab in (1,3,4) then cross_age=last.age; else if diab=2 then cross_age=first.age; run; Thanks!

Removing observations using matched group

How to extract visit using date of incident?

Re: creating new variable from possible combinations of other variable...

creating new variable from possible combinations of other variables

Re: Removing observations using matched group

Re: How to extract visit using date of incident?

Removing observations using matched group

How to extract visit using date of incident?

Re: creating new variable from possible combinations of other variable...

creating new variable from possible combinations of other variables