Two-piecewise Random Coefficient Model Using Proc Mixed
نویسنده
چکیده
In clinical research, the longitudinal data is gaining popularity. A pre-test is used as the baseline to minimize variation cross subjects. The example in this paper will show that repeated measures are taken not only after treatment but also before treatment with uneven time spaces. Two-piecewise random coefficient model is a powerful tool to model trends corresponding to time before and after treatment. The effect of treatment can be investigated by comparing two trends. In PROC MIXED, two-piecewise random coefficient model can be easily accomplished.
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تاریخ انتشار 2010