Hello. I'm working on a clinical trial dataset and am soliciting help as I try to analyze the data. I've done a fair amount with my (rudimentary) SAS skills, but have hit a few roadblocks. From 2465 patients in several clinical trials, I have a measure for a walk of time in seconds ( ~48000 observations). This measure is done twice per visit (order is not consequential) and different patients have different numbers of visits. The 2 outcomes at each visit should be averaged to create a single value. Abbreviated, and simple, dataset attached: USUBJID, visit date and walk time. I am seeking: 1) A dataset that has only the average time for each patient for each visit and the date for the visit. Long form. I have created average values for the baseline visit, but can't figure out how to do this across all visits. 2) Variables indicating whether the walk time increases for each patient, the amount of increase, and the date this occurred. Broad form - one record by USUBJID. Would be represented by an increase at any visit after baseline that is greater than 20% compared to baseline. If it happens multiple times, I only need the first occurrence. Again, since the dates for visits are all different for each patient, I am not sure how to approach. 3) To indicate a confirmed increase in walk times for each USUBJID. Broad form. This gets a bit complicated. This variable would be "positive" if there is an increase at any visit after baseline that is greater than 20% compared to baseline AND is sustained. Being sustained means that it is confirmed to be equal than or greater than the increased value >= 3 months after the initial increase and that there are no decreases during interval visits. 4) Isolate the last visit outcome (average of two measures) for each patient and the associated date of the last visit. I know this is a lot, so if anyone wants to help me tackle any specific aspect, I'd be so very appreciative! So much learning...:) Thank you.
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