TY - GEN AU - Reich,Nicholas G AU - Myers,Jessica A AU - Obeng,Daniel AU - Milstone,Aaron M AU - Perl,Trish M TI - Empirical power and sample size calculations for cluster-randomized and cluster-randomized crossover studies SN - 1932-6203 PY - 2012///0913 KW - Cluster Analysis KW - Cross-Over Studies KW - Humans KW - Internet KW - Models, Statistical KW - Randomized Controlled Trials as Topic KW - statistics & numerical data KW - Sample Size KW - Software N1 - Publication Type: Journal Article; Research Support, U.S. Gov't, Non-P.H.S.; Research Support, U.S. Gov't, P.H.S UR - https://doi.org/10.1371/journal.pone.0035564 ER -