Randomization in Clinical Trials

Rosenberger, William F.; Lachin, John M.

doi:10.1002/0471722103

Cited by 396 publications

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“…Randomisation was simple and, therefore, not restricted in any way. Simple randomisation reduces the risk of any possible subversion associated with restricted randomisation methods and has been shown to produce equally precise results 28 as stratified randomisation, which improves treatment precision in trials with fewer than 50 participants. However, simple randomisation can lead to unequal group sizes by chance alone.…”

Section: Randomisationmentioning

confidence: 99%

A randomised controlled trial of computerised cognitive behaviour therapy for the treatment of depression in primary care: the Randomised Evaluation of the Effectiveness and Acceptability of Computerised Therapy (REEACT) trial

Littlewood

Duarte

Hewitt

et al. 2015

Health Technol Assess

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BackgroundComputerised cognitive behaviour therapy (cCBT) has been developed as an efficient form of therapy delivery with the potential to enhance access to psychological care. Independent research is needed which examines both the clinical effectiveness and cost-effectiveness of cCBT over the short and longer term.ObjectivesTo compare the clinical effectiveness and cost-effectiveness of cCBT as an adjunct to usual general practitioner (GP) care against usual GP care alone, for a free-to-use cCBT program (MoodGYM; National Institute for Mental Health Research, Australian National University, Canberra, Australia) and a commercial pay-to-use cCBT program (Beating the Blues®; Ultrasis, London, UK) for adults with depression, and to determine the acceptability of cCBT and the experiences of users.DesignA pragmatic, multicentre, three-armed, parallel, randomised controlled trial (RCT) with concurrent economic and qualitative evaluations. Simple randomisation was used. Participants and researchers were not blind to treatment allocation.SettingPrimary care in England.ParticipantsAdults with depression who scored ≥ 10 on the Patient Health Questionnaire-9 (PHQ-9).InterventionsParticipants who were randomised to either of the two intervention groups received cCBT (Beating the Blues or MoodGYM) in addition to usual GP care. Participants who were randomised to the control group were offered usual GP care.Main outcome measuresThe primary outcome was depression at 4 months (PHQ-9). Secondary outcomes were depression at 12 and 24 months; measures of mental health and health-related quality of life at 4, 12 and 24 months; treatment preference; and the acceptability of cCBT and experiences of users.ResultsClinical effectiveness:210 patients were randomised to Beating the Blues, 242 patients were randomised to MoodGYM and 239 patients were randomised to usual GP care (total 691). There was no difference in the primary outcome (depression measured at 4 months) either between Beating the Blues and usual GP care [odds ratio (OR) 1.19, 95% confidence interval (CI) 0.75 to 1.88] or between MoodGYM and usual GP care (OR 0.98, 95% CI 0.62 to 1.56). There was no overall difference across all time points for either intervention compared with usual GP care in a mixed model (Beating the Blues versus usual GP care,p = 0.96; and MoodGYM versus usual GP care,p = 0.11). However, a small but statistically significant difference between MoodGYM and usual GP care at 12 months was found (OR 0.56, 95% CI 0.34 to 0.93). Free-to-use cCBT (MoodGYM) was not inferior to pay-to-use cCBT (Beating the Blues) (OR 0.91, 90% CI 0.62 to 1.34;p = 0.69). There were no consistent benefits of either intervention when secondary outcomes were examined. There were no serious adverse events thought likely to be related to the trial intervention. Despite the provision of regular technical telephone support, there was low uptake of the cCBT programs.Cost-effectiveness:cost-effectiveness analyses suggest that neither Beating the Blues nor MoodGYM appeared cost-effective compared with usual GP care alone.Qualitative evaluation:participants were often demotivated to access the computer programs, by reason of depression. Some expressed the view that a greater level of therapeutic input would be needed to promote engagement.ConclusionsThe benefits that have previously been observed in developer-led trials were not found in this large pragmatic RCT. The benefits of cCBT when added to routine primary care were minimal, and uptake of this mode of therapy was relatively low. There remains a clinical and economic need for effective low-intensity psychological treatments for depression with improved patient engagement.Trial registrationThis trial is registered as ISRCTN91947481.FundingThis project was funded by the National Institute for Health Research Health Technology Assessment programme.

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Section: Randomisationmentioning

confidence: 99%

A randomised controlled trial of computerised cognitive behaviour therapy for the treatment of depression in primary care: the Randomised Evaluation of the Effectiveness and Acceptability of Computerised Therapy (REEACT) trial

Littlewood

Duarte

Hewitt

et al. 2015

Health Technol Assess

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“…It is worth remarking on the form of the test statistic in (1). The quantity i ij (n)(p n; i −p n; j ) can be expressed equivalently as (a) the linear rank statistic given in Chapter 11 of Rosenberger and Lachin [28], and (b) a statistic that depends on the limiting allocation and the treatment di erence. The adaptive designs which will be described in Section 3 have di erent target allocations.…”

Section: Description Of Sequential Proceduresmentioning

confidence: 99%

Sequential urn designs with elimination for comparingK3 treatments

Coad

Ivanova

2005

Statist. Med.

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A fully sequential procedure is proposed for comparing K > or =3 treatments with immediate binary responses. The procedure uses an adaptive urn design to randomize patients to the treatments and stopping rules are incorporated for eliminating less promising treatments. Simulation is used to assess the performance of the procedure for several adaptive urn designs, in terms of expected numbers of treatment failures and allocation proportions, and the effect on estimation at the end of the trial is also addressed. It is concluded that the drop-the-loser rule is more effective than equal allocation and all of the other designs considered. The practical benefits of the procedure are illustrated using the results of a three-treatment lung cancer study. It is then shown how the sequential elimination procedure may be used in dose-finding studies and its performance is compared with a recently proposed method. Several possible extensions to the work are briefly indicated.

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“…Rosenberger and Lachin (2) give an up-to-date comprehensive exposition. This article will describe how a permutation test works in the simple context of comparing two groups, a treatment group and a control group, but the idea applies more generally to multi-arm trials.…”

Section: Permutation Tests-how They Workmentioning

confidence: 99%

Permutation Tests in Clinical Trials

Zucker¹

2014

Methods and Applications of Statistics in Clinical Trials

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Randomization in Clinical Trials

Cited by 396 publications

References 0 publications

A randomised controlled trial of computerised cognitive behaviour therapy for the treatment of depression in primary care: the Randomised Evaluation of the Effectiveness and Acceptability of Computerised Therapy (REEACT) trial

A randomised controlled trial of computerised cognitive behaviour therapy for the treatment of depression in primary care: the Randomised Evaluation of the Effectiveness and Acceptability of Computerised Therapy (REEACT) trial

Sequential urn designs with elimination for comparingK3 treatments

Permutation Tests in Clinical Trials

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