I am trying to calculate the most common combination of tests combination and test results, For example I would like to know the count of how many times Test_1 was taken with Test_2 and both positive... There is over 300+ samples with over 100+ tests, and it has been difficult to find a solution/code on how to simply output this. I've tried proc freq to get the individual counts, but that only gets me so far. Any advice?       Sample ID Test_1 Test_2 Test_3 1 positive positive negative 2 positive positive negative 3 negative negative negative 4 negative negative positive           ... View more