Design and Analysis of Group-Randomized Trials in Cancer: A Review of Current Practices

Murray, David M.; Pals, Sherri; Blitstein, Jonathan; Alfano, Catherine M.; Lehman, Jennifer

doi:10.1093/jnci/djn066

Cited by 79 publications

(81 citation statements)

References 112 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Proportions of trials in which clustering was accounted for in the sample size and analysis (Table 4) were similar to those for cluster randomised trials in all fields [12], and in the fields of tropical disease and oncology [11,38], but lower than in other areas [4,24,27]. Relative to previous reviews, we judged that identification/recruitment bias was possible in a lower percentage (7%) and unclear in a higher percentage (32%) of our included trials [4,27].…”

Section: Discussionmentioning

confidence: 85%

A systematic review of cluster randomised trials in residential facilities for older people suggests how to improve quality

Díaz-Ordaz

Froud

Sheehan

et al. 2013

BMC Med Res Methodol

View full text Add to dashboard Cite

BackgroundPrevious reviews of cluster randomised trials have been critical of the quality of the trials reviewed, but none has explored determinants of the quality of these trials in a specific field over an extended period of time. Recent work suggests that correct conduct and reporting of these trials may require more than published guidelines. In this review, our aim was to assess the quality of cluster randomised trials conducted in residential facilities for older people, and to determine whether (1) statistician involvement in the trial and (2) strength of journal endorsement of the Consolidated Standards of Reporting Trials (CONSORT) statement influence quality.MethodsWe systematically identified trials randomising residential facilities for older people, or parts thereof, without language restrictions, up to the end of 2010, using National Library of Medicine (Medline) via PubMed and hand-searching. We based quality assessment criteria largely on the extended CONSORT statement for cluster randomised trials. We assessed statistician involvement based on statistician co-authorship, and strength of journal endorsement of the CONSORT statement from journal websites.Results73 trials met our inclusion criteria. Of these, 20 (27%) reported accounting for clustering in sample size calculations and 54 (74%) in the analyses. In 29 trials (40%), methods used to identify/recruit participants were judged by us to have potentially caused bias or reporting was unclear to reach a conclusion. Some elements of quality improved over time but this appeared not to be related to the publication of the extended CONSORT statement for these trials. Trials with statistician/epidemiologist co-authors were more likely to account for clustering in sample size calculations (unadjusted odds ratio 5.4, 95% confidence interval 1.1 to 26.0) and analyses (unadjusted OR 3.2, 1.2 to 8.5). Journal endorsement of the CONSORT statement was not associated with trial quality.ConclusionsDespite international attempts to improve methods in cluster randomised trials, important quality limitations remain amongst these trials in residential facilities. Statistician involvement on trial teams may be more effective in promoting quality than further journal endorsement of the CONSORT statement. Funding bodies and journals should promote statistician involvement and co-authorship in addition to adherence to CONSORT guidelines.

show abstract

Section: Discussionmentioning

confidence: 85%

A systematic review of cluster randomised trials in residential facilities for older people suggests how to improve quality

Díaz-Ordaz

Froud

Sheehan

et al. 2013

BMC Med Res Methodol

View full text Add to dashboard Cite

show abstract

“…[35][36][37][38][39][40][41][42] For example, the unit of analysis error (where results were analysed without accounting for the clustering) was seen in 19/40 (48%) of medical care trials, 35 and among 75 reports of cluster trials in cancer prevention and control a third (34%) "failed to report any analyses that were judged to be appropriate." 37 Among 50 reports of cluster trials of screening interventions, 32 (64%) reported using a method of analysis that took account of clustering, but in several the method used was not stated explicitly.…”

Section: Discussionmentioning

confidence: 99%

Consort 2010 statement: extension to cluster randomised trials

Campbell

Piaggio

Elbourne

et al. 2012

BMJ

2,015

1,492

View full text Add to dashboard Cite

show abstract

“…Group-Randomized Trials (GRTs) are widely used for comparative studies when randomization at the individual level is not possible without substantial risk of contamination [1]. In a GRT, groups of subjects (e.g., schools, clinics, communities) are randomized to study groups, while outcomes are measured at the individual level.…”

Section: Introductionmentioning

confidence: 99%

“…Both GRTs and IRGT trials are commonly used study designs for intervention research and are employed across a range of disciplines [1, 4, 5]. There is a vast literature on the design and analysis of GRTs [2, 3], while there are far fewer publications on the methodologic challenges of IRGT trials [e.g., 6, 7, 8, 9].…”

Section: Introductionmentioning

confidence: 99%

Analytic methods for individually randomized group treatment trials and group-randomized trials when subjects belong to multiple groups

et al. 2014

View full text Add to dashboard Cite

Participants in trials may be randomized either individually or in groups, and may receive their treatment either entirely individually, entirely in groups, or partially individually and partially in groups. This paper concerns cases in which participants receive their treatment either entirely or partially in groups, regardless of how they were randomized. Participants in Group-Randomized Trials (GRTs) are randomized in groups and participants in Individually Randomized Group Treatment (IRGT) trials are individually randomized, but participants in both types of trials receive part or all of their treatment in groups or through common change agents. Participants who receive part or all of their treatment in a group are expected to have positively correlated outcome measurements. This paper addresses a situation that occurs in GRTs and IRGT trials – participants receive treatment through more than one group. As motivation, we consider trials in The Childhood Obesity Prevention and Treatment Research Consortium (COPTR), in which each child participant receives treatment in at least two groups. In simulation studies we considered several possible analytic approaches over a variety of possible group structures. A mixed model with random effects for both groups provided the only consistent protection against inflated type I error rates and did so at the cost of only moderate loss of power when intraclass correlations were not large. We recommend constraining variance estimates to be positive and using the Kenward-Roger adjustment for degrees of freedom; this combination provided additional power but maintained type I error rates at the nominal level.

show abstract

Design and Analysis of Group-Randomized Trials in Cancer: A Review of Current Practices

Cited by 79 publications

References 112 publications

A systematic review of cluster randomised trials in residential facilities for older people suggests how to improve quality

A systematic review of cluster randomised trials in residential facilities for older people suggests how to improve quality

Consort 2010 statement: extension to cluster randomised trials

Analytic methods for individually randomized group treatment trials and group-randomized trials when subjects belong to multiple groups

Contact Info

Product

Resources

About