when one is not enough: randomisation by community
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When One is Not Enough: Randomisation by Community. Neal Alexander. Why randomise by community or cluster Historical development of cluster-randomised trials Emphasis on infectious diseases Recent and current contributions of TEG. Outline. - PowerPoint PPT PresentationTRANSCRIPT
When One is Not Enough:Randomisation by Community
Neal Alexander
Why randomise by community or clusterHistorical development of cluster-randomised trials
Emphasis on infectious diseases
Recent and current contributions of TEG
Outline
Rationale: some interventions are difficult or impossible to allocate or assess individually
Freeman et al 2012 TMIH
Infections are ‘dependent happenings’
Pollock 1966 WHO monograph
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Cluster-randomized Trials in PubMed
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Cluster-randomized Trials in PubMed
Ferebee et al (1963): isoniazid prophylaxis in mental institutions
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Cluster-randomized Trials in PubMedThe Gambia Hepatitis Intervention Study (1987)
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Cluster-randomized Trials in PubMedBednets in Gambian villages (Snow et al 1988)
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Cluster-randomized Trials in PubMedIndirect effects (Halloran et al 1991)
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Cluster-randomized Trials in PubMed
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Management of STDs for HIV(Grosskurth et al 1995)
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Lancet 2009
Compares: community-wide isoniazid preventive therapy vs standard of TB care
1ary endpoint: TB incidence over 12 monthsResults unveiled at CROI 2012 by Fielding & Churchyard
Hostels Mine shaft
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Design & Analysis of Trials to Compare Genetic Selection Coefficients
Spatial Analysis of ‘Spillover’
Anaya-Izquierdo et al in prep; trial in Kroeger et al BMJ 2002
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