Cluster randomisation

In some cases it can be more convenient or appropriate not to randomise individual patients, but to randomise groups of patients. The groups for example 

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Bland (2004) provides a review and some examples of cluster randomised trials while Campbell, Donner and Klar (2007) give a comprehensive review of the methodology. 

Arani RB, Soong S-1, Weiss HL, Wood Ml et al. (2001) Phase specific analysis of herpes zoster associated pain data a new statistical approach Statistics in Medicine, 20, 2429-2439 Bedikian AY, MiUward M, Pehamberger H, Conry R et al. (2006) Bcl-2 Antisense (obUmersen sodium) plus dacarbazine in patients with advanced melanoma The ObUmersen Melanoma Study Group Journal of Clinical Oncology, 24, 4738-4745 Bland M (2004) Cluster randomised trials in the medical Uterature two bibliometric surveys BMC Medical Research Methodology, 4, 21... 

Byar DP (1980) Why data bases should not replace randomised trials Biometrics, 36, 337-342 Campbell MJ, Donner A and Klar N (2007) Developments in cluster randomised trials and Statistics in Medicine Statistics in Medicine, 26, 2-19 Coronary Drug Project Research Group (1980) Influence and adherence to treatment and response of cholesterol on mortality in the coronary drug project New England Journal of Medicine, 303, 1038-1041... 

Campbell, M.K., Elboume, D.R., Altman, D.G., for the CONSORT Group, 2004, CONSORT statement Extension to cluster randomised trials, British Medical Journal, 328 702-708. 

Watson, M.C. Bond, C. Grimshaw, J.M. Molli.son, J. Ludbrook, A. Educational Strategies to Promote Evidence-Based Practice A Cluster Randomised Controlled Trial (RCT). In Health Services Research and Pharmacy Practice Conference Proceedings, 2001. 

Olsen OE, Myklebust G, Engebretsen L, Holme I, Bahr R (2005) Exercises to prevent lower limb injuries in youth sports cluster randomised controlled trial. BMJ 33(X7489) 449... 

Kritsidima, M., Newton, T., Asimakopoulou, K. 2010. The effects of lavender scent on dental patient anxiety levels A cluster randomised-controlled trial. 38(l) 83-87. 

Morris, Saul, Rafael Flores, Pedro Olinto, and Juan Manuel Medina. 2004. Monetary Incentives in Primary Health Care and Effects on Use and Coverage of Preventive Health Care Interventions in Rural Honduras Cluster Randomised Trial. Lancet 364 (9450) 2030—37. 

Milstone AM, Elward A, Song X, Zerr DM, Orschebi R, Speck K, et al. Daily chlorhexidine bathing to reduce bacteraemia in critically iU children a multicentre, cluster-randomised, crossover trial. Lancet 2013 381(9872) 1099-106. 

V. Chen-Hussey, I. Carneiro, H. Keomanila, R. Gray, S. Bannavong, S. Phanalasy, and S. W. Lindsay. Can topical insect repellents reduce malaria A cluster-randomised controlled trial of the insect repellent N,N-diethyl-m-toluamide (DEET) in Lao PDR, PLoS One, 8, e70664, 2013. 

W. Deressa, Y. Y. Yihdego, Z. Kebede, E. Batisso, A. Tekalegne, and G. A. Dagne. Effect of combining mosquito repellent and insecticide treated net on malaria prevalence in southern Ethiopia A cluster-randomised triaL Parasites and Vectors, 1, 132, 2014. 

Order or disorder of defects is a matter of a fine balance between the configurational entropy of the defects and the exothermic enthalpy gained in association of certain point defects to form various t) es of larger defect agglomerations. Systems with relatively small defect concentrations are entropy controlled and consist of randomly distributed point defects. As concentration increases the enthalpy takes control and leads successively to formation of larger defect entities randomised associated defects or defect clusters, point defects assimilated into randomised stmcture elements of a new phase, superlattice ordering and extended defects, shear planes, and discrete intermediate phases. 

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