TY - JOUR
T1 - Understanding Statistical Power in Cluster Randomized Trials
T2 - Challenges Posed by Differences in Notation and Terminology
AU - Spybrook, Jessaca
AU - Hedges, Larry
AU - Borenstein, Michael
N1 - Funding Information:
In the past decade, the capacity of researchers to design adequately powered CRTs has improved. Spybrook and Raudenbush (2009) examined the power analyses of CRTs funded by the Institute of Education Sciences. In the early studies, such as those funded in 2002, the power analyses often lacked detailed and were not technically accurate. However, for the studies funded in 2006, the authors found that the power analyses were much more detailed and technically accurate. We expect that the power analyses researchers include with grant proposals today are even more accurate and detailed.
PY - 2014/10/15
Y1 - 2014/10/15
N2 - Abstract: Research designs in which clusters are the unit of randomization are quite common in the social sciences. Given the multilevel nature of these studies, the power analyses for these studies are more complex than in a simple individually randomized trial. Tools are now available to help researchers conduct power analyses for cluster randomized trials. A key challenge facing researchers in using the tools is that different tools use different language, notation, and design parameters. This makes it difficult for researchers to communicate about the steps for a power analysis or to evaluate the appropriateness of a power analysis. This article provides explicit connections between the language, notation, and design parameters of two widely used approaches and tools for conducting power analyses, Optimal Design Plus and CRT Power. The formulas for translating design parameters between the two programs are provided and the comparability of the two programs is illustrated.
AB - Abstract: Research designs in which clusters are the unit of randomization are quite common in the social sciences. Given the multilevel nature of these studies, the power analyses for these studies are more complex than in a simple individually randomized trial. Tools are now available to help researchers conduct power analyses for cluster randomized trials. A key challenge facing researchers in using the tools is that different tools use different language, notation, and design parameters. This makes it difficult for researchers to communicate about the steps for a power analysis or to evaluate the appropriateness of a power analysis. This article provides explicit connections between the language, notation, and design parameters of two widely used approaches and tools for conducting power analyses, Optimal Design Plus and CRT Power. The formulas for translating design parameters between the two programs are provided and the comparability of the two programs is illustrated.
KW - Research design
KW - cluster randomized trials
KW - statistical power
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U2 - 10.1080/19345747.2013.848963
DO - 10.1080/19345747.2013.848963
M3 - Article
AN - SCOPUS:84911965840
VL - 7
SP - 384
EP - 406
JO - Journal of Research on Educational Effectiveness
JF - Journal of Research on Educational Effectiveness
SN - 1934-5747
IS - 4
ER -