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Run-Reversal Equilibrium for Clinical Trial Randomization.

Grant WC - PLoS ONE (2015)

Bottom Line: In this paper, we describe a new restricted randomization method called run-reversal equilibrium (RRE), which is a Nash equilibrium of a game where (1) the clinical trial statistician chooses a sequence of medical treatments, and (2) clinical investigators make treatment predictions.RRE randomization counteracts how each investigator could observe treatment histories in order to forecast upcoming treatments.Computation of a run-reversal equilibrium reflects how the treatment history at a particular site is imperfectly correlated with the treatment imbalance for the overall trial.

View Article: PubMed Central - PubMed

Affiliation: Department of Economics, James Madison University, Harrisonburg VA, United States of America; Visiting Faculty, Duke Clinical Research Institute, Durham NC, United States of America.

ABSTRACT
In this paper, we describe a new restricted randomization method called run-reversal equilibrium (RRE), which is a Nash equilibrium of a game where (1) the clinical trial statistician chooses a sequence of medical treatments, and (2) clinical investigators make treatment predictions. RRE randomization counteracts how each investigator could observe treatment histories in order to forecast upcoming treatments. Computation of a run-reversal equilibrium reflects how the treatment history at a particular site is imperfectly correlated with the treatment imbalance for the overall trial. An attractive feature of RRE randomization is that treatment imbalance follows a random walk at each site, while treatment balance is tightly constrained and regularly restored for the overall trial. Less predictable and therefore more scientifically valid experiments can be facilitated by run-reversal equilibrium for multi-site clinical trials.

No MeSH data available.


Related in: MedlinePlus

Urn Design for Run-Reversal Equilibrium with 3 Clinics.An urn is selected according to the probabilities shown, and then balls are drawn without replacement until the urn is empty. A run in treatment imbalance is assigned for a clinic when a white ball is drawn. A reversal in treatment imbalance is assigned for a clinic when a black ball is drawn.
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pone.0128812.g001: Urn Design for Run-Reversal Equilibrium with 3 Clinics.An urn is selected according to the probabilities shown, and then balls are drawn without replacement until the urn is empty. A run in treatment imbalance is assigned for a clinic when a white ball is drawn. A reversal in treatment imbalance is assigned for a clinic when a black ball is drawn.

Mentions: The random-walk property can be depicted with repeated draws from urns of black and white balls. For the RRE derived in section 2.3, Fig 1 shows two urns, each of which is filled with three balls. Imagine that the statistician first chooses one of the urns, and subsequently, the statistician selects a clinic-x ball from the chosen urn, then selects a clinic-y ball from the same chosen urn (without replacing the first ball), and then draws a final clinic-z ball from the same chosen urn (without replacing the first two balls). Ball color indicates whether or not a clinic’s treatment imbalance gets reversed. Each clinic assigned a white ball experiences a run in treatment imbalance, while each clinic assigned a black ball experiences a reversal in treatment imbalance.


Run-Reversal Equilibrium for Clinical Trial Randomization.

Grant WC - PLoS ONE (2015)

Urn Design for Run-Reversal Equilibrium with 3 Clinics.An urn is selected according to the probabilities shown, and then balls are drawn without replacement until the urn is empty. A run in treatment imbalance is assigned for a clinic when a white ball is drawn. A reversal in treatment imbalance is assigned for a clinic when a black ball is drawn.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4469309&req=5

pone.0128812.g001: Urn Design for Run-Reversal Equilibrium with 3 Clinics.An urn is selected according to the probabilities shown, and then balls are drawn without replacement until the urn is empty. A run in treatment imbalance is assigned for a clinic when a white ball is drawn. A reversal in treatment imbalance is assigned for a clinic when a black ball is drawn.
Mentions: The random-walk property can be depicted with repeated draws from urns of black and white balls. For the RRE derived in section 2.3, Fig 1 shows two urns, each of which is filled with three balls. Imagine that the statistician first chooses one of the urns, and subsequently, the statistician selects a clinic-x ball from the chosen urn, then selects a clinic-y ball from the same chosen urn (without replacing the first ball), and then draws a final clinic-z ball from the same chosen urn (without replacing the first two balls). Ball color indicates whether or not a clinic’s treatment imbalance gets reversed. Each clinic assigned a white ball experiences a run in treatment imbalance, while each clinic assigned a black ball experiences a reversal in treatment imbalance.

Bottom Line: In this paper, we describe a new restricted randomization method called run-reversal equilibrium (RRE), which is a Nash equilibrium of a game where (1) the clinical trial statistician chooses a sequence of medical treatments, and (2) clinical investigators make treatment predictions.RRE randomization counteracts how each investigator could observe treatment histories in order to forecast upcoming treatments.Computation of a run-reversal equilibrium reflects how the treatment history at a particular site is imperfectly correlated with the treatment imbalance for the overall trial.

View Article: PubMed Central - PubMed

Affiliation: Department of Economics, James Madison University, Harrisonburg VA, United States of America; Visiting Faculty, Duke Clinical Research Institute, Durham NC, United States of America.

ABSTRACT
In this paper, we describe a new restricted randomization method called run-reversal equilibrium (RRE), which is a Nash equilibrium of a game where (1) the clinical trial statistician chooses a sequence of medical treatments, and (2) clinical investigators make treatment predictions. RRE randomization counteracts how each investigator could observe treatment histories in order to forecast upcoming treatments. Computation of a run-reversal equilibrium reflects how the treatment history at a particular site is imperfectly correlated with the treatment imbalance for the overall trial. An attractive feature of RRE randomization is that treatment imbalance follows a random walk at each site, while treatment balance is tightly constrained and regularly restored for the overall trial. Less predictable and therefore more scientifically valid experiments can be facilitated by run-reversal equilibrium for multi-site clinical trials.

No MeSH data available.


Related in: MedlinePlus