Hi everyone, I came across this question in my working project. It does not seem to be a difficult task, but I just can not figure it out after spending the whole night, sigh....:smileyconfused: There are two datasets, one contains patients ID and one continuous biomarker variable x, the other dataset provides the reference range of this biomarker x (lowref_x and highref_x) and corresponded disease severity score for each range of x. Since there is no common variable between the two datasets I have to come up with some coding to generate the disease severity score for each patient ID based on his marker value in dataset one and reference range in dataset two. Can anyone help me out on this? I really appreciate it!! ... View more