The Limitations of RCT Data

There were 62 eligible RCTs and 16 long term extensions you have something like 82,500 person years of exposure to the Jack but only 3,000 person years to placebo 8,000 to TNF and 1,000 to miter treksate. Now if you have that difference inperson years of exposure is it going to make a bias for or against one group or the other? So that's a really good point  and this is always a problem when you're metaranalyzing RCT data where often particularly the placebo arms are both shorter and sort of less abundant in terms of people years of exposure.