Allocation techniques for balance at baseline in cluster randomized trials: a methodological review
<p>Abstract</p> <p>Reviews have repeatedly noted important methodological issues in the conduct and reporting of cluster randomized controlled trials (C-RCTs). These reviews usually focus on whether the intracluster correlation was explicitly considered in the design and analysis o...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2012-08-01
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| Series: | Trials |
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| Online Access: | http://www.trialsjournal.com/content/13/1/120 |
| _version_ | 1818556216428724224 |
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| author | Ivers Noah M Halperin Ilana J Barnsley Jan Grimshaw Jeremy M Shah Baiju R Tu Karen Upshur Ross Zwarenstein Merrick |
| author_facet | Ivers Noah M Halperin Ilana J Barnsley Jan Grimshaw Jeremy M Shah Baiju R Tu Karen Upshur Ross Zwarenstein Merrick |
| author_sort | Ivers Noah M |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Reviews have repeatedly noted important methodological issues in the conduct and reporting of cluster randomized controlled trials (C-RCTs). These reviews usually focus on whether the intracluster correlation was explicitly considered in the design and analysis of the C-RCT. However, another important aspect requiring special attention in C-RCTs is the risk for imbalance of covariates at baseline. Imbalance of important covariates at baseline decreases statistical power and precision of the results. Imbalance also reduces face validity and credibility of the trial results. The risk of imbalance is elevated in C-RCTs compared to trials randomizing individuals because of the difficulties in recruiting clusters and the nested nature of correlated patient-level data. A variety of restricted randomization methods have been proposed as way to minimize risk of imbalance. However, there is little guidance regarding how to best restrict randomization for any given C-RCT. The advantages and limitations of different allocation techniques, including stratification, matching, minimization, and covariate-constrained randomization are reviewed as they pertain to C-RCTs to provide investigators with guidance for choosing the best allocation technique for their trial.</p> |
| first_indexed | 2024-12-13T23:44:31Z |
| format | Article |
| id | doaj.art-b7270e490d784b23bfb28628fc390f27 |
| institution | Directory Open Access Journal |
| issn | 1745-6215 |
| language | English |
| last_indexed | 2024-12-13T23:44:31Z |
| publishDate | 2012-08-01 |
| publisher | BMC |
| record_format | Article |
| series | Trials |
| spelling | doaj.art-b7270e490d784b23bfb28628fc390f272022-12-21T23:27:03ZengBMCTrials1745-62152012-08-0113112010.1186/1745-6215-13-120Allocation techniques for balance at baseline in cluster randomized trials: a methodological reviewIvers Noah MHalperin Ilana JBarnsley JanGrimshaw Jeremy MShah Baiju RTu KarenUpshur RossZwarenstein Merrick<p>Abstract</p> <p>Reviews have repeatedly noted important methodological issues in the conduct and reporting of cluster randomized controlled trials (C-RCTs). These reviews usually focus on whether the intracluster correlation was explicitly considered in the design and analysis of the C-RCT. However, another important aspect requiring special attention in C-RCTs is the risk for imbalance of covariates at baseline. Imbalance of important covariates at baseline decreases statistical power and precision of the results. Imbalance also reduces face validity and credibility of the trial results. The risk of imbalance is elevated in C-RCTs compared to trials randomizing individuals because of the difficulties in recruiting clusters and the nested nature of correlated patient-level data. A variety of restricted randomization methods have been proposed as way to minimize risk of imbalance. However, there is little guidance regarding how to best restrict randomization for any given C-RCT. The advantages and limitations of different allocation techniques, including stratification, matching, minimization, and covariate-constrained randomization are reviewed as they pertain to C-RCTs to provide investigators with guidance for choosing the best allocation technique for their trial.</p>http://www.trialsjournal.com/content/13/1/120Cluster-randomized trialsBalanced allocationRestricted randomization |
| spellingShingle | Ivers Noah M Halperin Ilana J Barnsley Jan Grimshaw Jeremy M Shah Baiju R Tu Karen Upshur Ross Zwarenstein Merrick Allocation techniques for balance at baseline in cluster randomized trials: a methodological review Trials Cluster-randomized trials Balanced allocation Restricted randomization |
| title | Allocation techniques for balance at baseline in cluster randomized trials: a methodological review |
| title_full | Allocation techniques for balance at baseline in cluster randomized trials: a methodological review |
| title_fullStr | Allocation techniques for balance at baseline in cluster randomized trials: a methodological review |
| title_full_unstemmed | Allocation techniques for balance at baseline in cluster randomized trials: a methodological review |
| title_short | Allocation techniques for balance at baseline in cluster randomized trials: a methodological review |
| title_sort | allocation techniques for balance at baseline in cluster randomized trials a methodological review |
| topic | Cluster-randomized trials Balanced allocation Restricted randomization |
| url | http://www.trialsjournal.com/content/13/1/120 |
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