Hello,

I am using 10 yrs of hospital based data where people are admitted more than once within the 10 years. I am looking to only use the first admission, but do not know how to code or take that into account. Similarly, one of the variables is a clinical test that was performed and in some cases the test is performed multiple times in one admission period and I want to only include the test result on the first admission. I do not know how to code for that and would appreciate any and all help. Thank you!