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Andersen SW, Millen BA. On the practical application of mixed effects models for repeated measures to clinical trial data. Pharm Stat. 2013;12(1):7-16. Article available to OhioLINK patrons.
Bhaskaran K, Smeeth L. What is the difference between missing completely at random and missing at random? International Journal of Epidemiology. 2014;43(4):1336-1339.