Thank you all for your comments. Here is an example of the data I am considering. id cat test result date 1 chd wgt y 01/01/2016 1 chd hgt n 01/01/2016 1 chd wgt n 02/02/2016 2 chd wgt y 01/01/2016 2 chd wgt y 01/02/2016 2 chd hgt n 01/02/2016 . . . I need to know if at any point a patient had a "y" result, regardless of the test. Does that make sense? Thanks again!
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