Balance algorithm for cluster randomized trials.
BMC Med Res Methodol
; 8: 65, 2008 Oct 09.
Article
em En
| MEDLINE
| ID: mdl-18844993
ABSTRACT
BACKGROUND:
Within cluster randomized trials no algorithms exist to generate a full enumeration of a block randomization, balancing for covariates across treatment arms. Furthermore, often for practical reasons multiple blocks are required to fully randomize a study, which may not have been well balanced within blocks.RESULTS:
We present a convenient and easy to use randomization tool to undertake allocation concealed block randomization. Our algorithm highlights allocations that minimize imbalance between treatment groups across multiple baseline covariates. We demonstrate the algorithm using a cluster randomized trial in primary care (the PRE-EMPT Study) and show that the software incorporates a trade off between independent random allocations that were likely to be imbalanced, and predictable deterministic approaches that would minimise imbalance. We extend the methodology of single block randomization to allocate to multiple blocks conditioning on previous allocations.CONCLUSION:
The algorithm is included as Additional file 1 and we advocate its use for robust randomization within cluster randomized trials.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Algoritmos
/
Análise por Conglomerados
/
Ensaios Clínicos Controlados Aleatórios como Assunto
Tipo de estudo:
Clinical_trials
/
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article