I basically want participants to be asked a series of follow-up questions only if they respond "yes" to one or more questions about their drug use. So for instance, if they answer yes to question 15, 16, or 17, I'd like questions#18-20 to be asked, but if they answer "no" to all three (q15, 16, AND 17), I'd like questions 18-20 to be skipped. To do this, I assigned {0} values to all the "No" responses and had excel sum the results of q#15-17, such that if the sum is less than 1, it should skip the subsequent questions (18-20). It works fine if they answer yes to any of the three questions, but it won't read the skip pattern if the sum of the question responses is 0 (i.e., they answered no to 15, 16, and 17). This same process applies to the other skip patterns in the excel file, so I'm assuming it's something I'm doing wrong, but I just can't figure out what it is...