REFERENCES
- Casella , G , Berger , R. L. ( 2002 ). Statistical Inference, , 2nd ed. Pacific Grove , CA : Duxbury .
- Cochran , W. G. ( 1977 ). Sampling Techniques, , 3rd ed. New York : Wiley .
- Fienberg , S. E. , Tanur , J. M. ( 1987 ). Experimental and sampling structure: Parallels, diverging and meeting . International Statistical Review 55 : 75 – 96 .
- Kim , K. M. , DeMets , D. L. ( 1992 ). Sample-size determination for group sequential clinical trials with immediate response . Statistics in Medicine 11 : 1391 – 1399 .
- Levy , P. S. , Lemeshow , S. ( 1999 ). Sampling of Populations: Methods and Applications, , 3rd ed. New York : Wiley .
- Lin , Z. ( 1999 ). An issue of statistical analysis in controlled multi-center studies: How shall we weight the centers . Statistics in Medicine 18 : 365 – 373 .
- Moye , L. A. ( 1997 ). Sizing clinical trials with variable endpoint event rates . Statistics in Medicine 20 : 2267 – 2282 .
- Revuna , F. ( 2004 ). Unequal center size, sample size, and power in multicenter clinical trials . Drug Information Journal 38 : 387 – 394 .
- Senn , S. ( 1998 ). Some controversies in planning and analyzing multi-centre trials . Statistics in Medicine 17 : 1753 – 1765 .
- Vierron , E. , Giraudeau , B. ( 2007 ). Sample size calculation for multicenter randomized trial: Taking the center effect into account . Contemporary Clinical Trials 28 : 451 – 458 .